QUESTIONS AND ANSWERS ABOUT THE MERGER AND THE SPECIAL MEETING

The following are some questions that you may have regarding the Agreement and Plan of Reorganization, dated as of July 23, 2015, by and between Independent Bank Group, Inc., or Independent, and Grand Bank, and the special meeting, and brief answers to those questions. Independent and Grand Bank advise you to read carefully the remainder of this proxy statement/prospectus because the information contained in this section does not provide all of the information that might be important to you with respect to the merger and the special meeting. Additional important information is also referred to under the caption “Where You Can Find More Information” beginning on page 102.

No other business may be conducted at the special meeting.

As noted above, pursuant to the terms of the reorganization agreement, the amount of aggregate cash consideration paid by Independent to shareholders of Grand Bank will also be reduced by the aggregate amount of cash paid by Independent to the holders of options to purchase shares of Grand Bank common stock who have irrevocably agreed to surrender their options in exchange for a cash payment equal to the difference between the aggregate value of the shares subject to their options (as determined pursuant to the reorganization agreement) and the aggregate exercise price for such options. The reorganization agreement provides that the value of the shares subject to the options to be surrendered for a cash payment will be based upon the value of the per share stock consideration. This value will be calculated using the average of the daily volume weighted average sale price per share of Independent common stock on The NASDAQ Stock Market, Inc. Global Select Market System for the ten consecutive trading days ending on and including the third trading day preceding the closing date reported by Bloomberg, or the average sales price. The holders of options to purchase an aggregate of 127,156 shares of Grand Bank common stock have elected to receive such cash payment. Based upon this election and the closing price of Independent common stock on September 22, 2015 of $39.49, Independent would pay an aggregate of approximately $1.8 million in cash to such option holders. In that event, the aggregate amount of cash consideration to be paid by Independent to Grand Bank shareholders would be reduced by approximately $1.8 million. The $12.22 per share cash consideration to be paid to Grand Bank shareholders set forth above reflects this adjustment. The average sales price will fluctuate prior to the closing date and the option payment amount will not be determined until the third trading day prior to the closing date. For this reason, the amount of adjustment to the cash portion of the merger consideration resulting from the option payment may be more or less than the amount set forth above.

If the average sales price is less than 90% of $43.7660, or $39.3894, the per share stock consideration would be adjusted to a fraction of a share of Independent common stock (rounded to the nearest ten thousandth) equal to the quotient of (x) $27.6270; divided by (y) the average sales price.

If the average sales price is more than 110% of $43.7660, or $48.1426, the per share stock consideration would be adjusted to a fraction of a share of Independent common stock (rounded to the nearest ten thousandth) equal to the quotient of (x) $33.7663; divided by (y) the average sales price.

Tangible book value will increase or decrease by the amount of net income or net loss, respectively, of Grand Bank through the closing date. Tangible book value will also increase by the amount of additional paid in capital resulting from the exercise of stock options. However, all costs and expenses of Grand Bank related to the merger will be included as a deduction in the calculation of Grand Bank’s tangible book value. For more detail about how Grand Bank’s tangible book value will be calculated pursuant to the reorganization agreement, see the section entitled “Proposal to Approve the Reorganization Agreement—Terms of the Merger” beginning on page 40. Management of Grand Bank estimates net income (before costs and expenses of the merger) of approximately $1.7 million from July 1, 2015, through October 31, 2015 (the estimated closing date), additional paid in capital of approximately $2.4 million resulting from the exercise of stock options, and aggregate merger-related deductions to tangible book value of approximately $5.6 million. If these assumptions are correct, the amount of Grand Bank’s tangible book value, as calculated pursuant to the reorganization agreement, would be approximately $40.0 million on the closing date. This amount is only an estimate and is based upon several assumptions, many of which are beyond the control of Grand Bank. Accordingly, the actual amount of Grand Bank’s tangible book value may vary from this estimated amount.

Item 1—FOR the approval of the reorganization agreement and the merger; and

Item 2—FOR the adjournment of the special meeting if the board of directors of Grand Bank determines an adjournment is necessary to permit further solicitation of additional proxies if there are not sufficient votes at the time of the special meeting to constitute a quorum or to approve the reorganization agreement.

As a record holder (that is, your shares of Grand Bank common stock are held in your own name), you may vote by proxy or you may attend the special meeting and vote in person. If you are a record holder on the record date for the special meeting and want to vote your shares by proxy, simply indicate on the proxy card(s) applicable to your shares of Grand Bank common stock how you want to vote and sign, date and mail your proxy card(s) in the enclosed pre-addressed postage-paid envelope as soon as possible, but in any event by such time that your proxy card may be received prior to the vote at the special meeting.

Your proxy card(s) must be received by Grand Bank by no later than the time the polls close for voting at the special meeting for your vote to be counted at the meeting.

Voting your shares by proxy will enable your shares of Grand Bank common stock to be represented and voted at the special meeting if you do not attend the special meeting and vote your shares in person.

SUMMARY

This summary highlights selected information from this proxy statement/prospectus and may not contain all of the information that is important to you. Independent urges you to carefully read this entire document and the other information that Independent refers to in this document. These documents will give you a more complete description of the items for consideration at the special meeting. For more information about Independent, see “Where You Can Find More Information” on page 102. Independent has included page references in this summary to direct you to other places in this proxy statement/prospectus where you can find a more complete description of the topics that Independent has summarized.

The Companies

Independent Bank Group, Inc.

1600 Redbud Boulevard, Suite 400

McKinney, Texas 75069-3257

(972) 562-9004

Independent, a Texas corporation, is a bank holding company registered under the Bank Holding Company Act of 1956, as amended, or the BHC Act. Through Independent Bank, its wholly owned subsidiary bank, which is a Texas state banking association, Independent provides a wide range of relationship driven, commercial banking products and services. Independent currently operates a total of 40 full-service banking centers in three regions in Texas: Dallas/North Texas, Austin/Central Texas, and Houston. As of June 30, 2015, on a consolidated basis, Independent had total assets of $4.4 billion, total loans of $3.4 billion, total deposits of $3.5 billion and shareholders’ equity of $559.4 million.

Grand Bank

16660 Dallas Parkway, Suite 1700

Dallas, Texas 75248

(972) 735-1000

Grand Bank, a Texas banking association, is a full service commercial bank with two branches located in the Dallas, Texas, metropolitan area. As of June 30, 2015, Grand Bank had total assets of $608.6 million, total deposits of $507.1 million, total net loans of $246.3 million and total shareholders’ equity of $41.6 million.

Proposed Merger

Independent has attached the reorganization agreement to this document as Appendix A. Please read the entire reorganization agreement, which includes the related agreement and plan of merger, attached thereto as Exhibit A. They are the legal documents that govern the merger.

The reorganization agreement provides that Grand Bank will be merged with and into Independent Bank with Independent Bank being the surviving bank. Grand Bank will cease to exist after the merger occurs. The existing locations of Grand Bank will become banking centers of Independent Bank. Independent expects to complete the merger in the fourth quarter of 2015, although delays could occur. The merger will be accounted for as an acquisition of Grand Bank by Independent and Independent Bank under the acquisition method of accounting in accordance with Financial Accounting Standard Board’s Accounting Standard Codification Topic 805, “Business Combinations.”

Terms of the Merger (page 40)

Aggregate Merger Consideration. Under the terms of the reorganization agreement, if the reorganization agreement is approved and the merger is completed, all outstanding shares of Grand Bank common stock will be

converted into an aggregate of $24.1 million in cash and 1,279,532 shares of Independent common stock, subject in each case to adjustment under certain circumstances as set forth in the reorganization agreement and described in this proxy statement/prospectus. Based upon the closing price of Independent common stock on September 22, 2015, of $39.49, and assuming that the tangible book value of Grand Bank is at least $40.0 million on the calculation date, the aggregate amount of the total merger consideration to be paid by Independent is valued at $72.8 million.

Per Share Merger Consideration. Based upon 1,824,304 shares anticipated to be outstanding immediately prior to the effective time of the merger, which includes 1,726,810 shares outstanding on September 18, 2015 and 97,494 shares to be issued upon the exercise of options to purchase shares of Grand Bank common stock held by Grand Bank option holders who have irrevocably agreed to exercise such options prior to the effective time of the merger and based upon the payment of a total of approximately $1.8 million to Grand Bank option holders who have irrevocably elected to receive a net cash payment for the surrender and cancellation of their options, which amount was calculated using the closing price of Independent common stock on September 22, 2015 of $39.49, holders of Grand Bank common stock will receive 0.7014 of a share of Independent common stock and $12.22 in cash, subject in each case to adjustment under certain circumstances as set forth in the reorganization agreement and described in this proxy statement/prospectus, for each share of Grand Bank common stock they own at the effective time of the merger.

Adjustment to Cash Consideration. The amount of aggregate cash consideration paid by Independent would be reduced if Grand Bank’s tangible book value, as calculated pursuant to the reorganization agreement, is less than $40.0 million but more than $39.0 million on the calculation date. Under those circumstances, the aggregate cash consideration would be reduced by the difference between $40.0 million and the amount of Grand Bank’s tangible book value on that date. In the event of such a reduction, the per share cash consideration would be reduced by an amount equal to the quotient of (i) the amount of the reduction in aggregate cash consideration, divided by (ii) 1,824,304, the number of shares of Grand Bank common stock expected to be outstanding on the closing date. If the tangible book value of Grand Bank is less than $39.0 million on the closing date, Independent would not be obligated to consummate the transaction.

As noted above, pursuant to the terms of the reorganization agreement, the amount of aggregate cash consideration paid by Independent to shareholders of Grand Bank will also be reduced by the aggregate amount of cash paid by Independent to the holders of options to purchase shares of Grand Bank common stock who have irrevocably agreed to surrender their options in exchange for a cash payment equal to the difference between the aggregate value of the shares subject to their options (as determined pursuant to the reorganization agreement) and the aggregate exercise price for such options. The reorganization agreement provides that the value of the shares subject to the options to be surrendered for a cash payment will be based upon the value of the per share stock consideration. This value will be calculated using the average of the daily volume weighted average sale price per share of Independent common stock on The NASDAQ Stock Market, Inc. Global Select Market System for the ten consecutive trading days ending on and including the third trading day preceding the closing date reported by Bloomberg, or the average sales price. The holders of options to purchase an aggregate of 127,156 shares of Grand Bank common stock have elected to receive such cash payment. Based upon this election and the closing price of Independent common stock on September 22, 2015 of $39.49, Independent would pay an aggregate of approximately $1.8 million in cash to such option holders. In that event, the aggregate amount of cash consideration to be paid by Independent to the Grand Bank shareholders would be reduced by approximately $1.8 million. The $12.22 per share cash consideration to be paid to Grand Bank shareholders set forth above reflects this adjustment. The average sales price will fluctuate prior to the closing date and the option payment amount will not be determined until the third trading day prior to the closing date. For this reason, the amount of adjustment to the cash portion of the merger consideration resulting from the option payment may be more or less than the amount set forth above.

Adjustment to Stock Consideration. The amount of aggregate stock consideration paid by Independent will be adjusted if the average sales price of Independent common stock is 10% more or 10% less than $43.7660.

If the average sales price is less than 90% of $43.7660, or $39.3894, the per share stock consideration would be adjusted to a fraction of a share of Independent common stock (rounded to the nearest ten thousandth) equal to the quotient of (x) $27.6270; divided by (y) the average sales price. If the average sales price is more than 110% of $43.7660, or $48.1426, the per share stock consideration would be adjusted to a fraction of a share of Independent common stock (rounded to the nearest ten thousandth) equal to the quotient of (x) $33.7663; divided by (y) the average sales price. Therefore, the maximum aggregate value of Independent common stock to be issued to Grand Bank shareholders is $61.6 million and the minimum aggregate value of Independent common stock to be issued to Grand Bank shareholders is $50.4 million. As of September 22, 2015, the closing sales price of Independent common stock was $39.49 per share.

Other Financial Aspects. If Grand Bank’s tangible book value is greater than $40.0 million on the calculation date, then on the day prior to the closing date, Grand Bank may distribute to its shareholders an amount equal to the difference between the actual amount of tangible book value on the calculation date minus $40.0 million.

Grand Bank’s tangible book value as calculated pursuant to the reorganization agreement was approximately $41.5 million as of June 30, 2015. Tangible book value will increase or decrease by the amount of net income or net loss, respectively, of Grand Bank through the closing date. Tangible book value will also increase by the amount of additional paid in capital resulting from the exercise of stock options. However, all costs and expenses of Grand Bank related to the merger will be included as a deduction in the calculation of tangible book value. For more detail about how Grand Bank’s tangible book value will be calculated pursuant to the reorganization agreement, see the section titled “Proposal to Approve the Reorganization Agreement—Terms of the Merger” beginning on page 40.

Fractional shares of Independent common stock will be paid in cash, without interest. The market price of Independent common stock will fluctuate from the date of this proxy statement/prospectus through the third trading date prior to the effective date of the merger, which is the date on which the per share stock consideration is determined for the merger. Because of the possibility of the tangible book value adjustment to the amount of the per share cash consideration and the fluctuation of the market price of Independent common stock that will comprise the per share stock consideration, you will not know the exact amount of cash or the exact number of shares of Independent common stock you will receive in connection with the merger when you vote on the reorganization agreement.

Material U.S. Federal Income Tax Consequences of the Merger (page 74)

The merger is intended to qualify as a reorganization within the meaning of Section 368(a) of the Internal Revenue Code, as amended, or the Code, for U.S. federal income tax purposes, and the closing is conditioned upon the receipt by Independent of an opinion from Andrews Kurth LLP, special counsel to Independent, to the effect that the merger so qualifies. This summary of U.S. federal income tax consequences assumes that the merger will be consummated as described in the reorganization agreement and this proxy statement/prospectus and that Independent will not waive the opinion condition described in “Proposal to Approve the Reorganization Agreement—Material U.S. Federal Income Tax Consequences of the Merger—Tax Opinion.” If the merger qualifies as such a reorganization, the material U.S. federal income tax consequences of the merger to U.S. holders of Grand Bank common stock will be as follows: holders of Grand Bank common stock generally will recognize gain (but not loss) with respect to their Grand Bank common stock. The gain a U.S. holder of Grand Bank common stock recognizes generally will be equal to the lesser of (i) the amount of cash consideration received in the merger (excluding any cash received in lieu of a fractional share of Independent common stock),

or (ii) the amount by which the cash consideration received in the merger for the Grand Bank common stock plus the stock consideration received in the merger (based upon the fair market value of the Independent common stock at the effective time of the merger) exceeds the adjusted tax basis in the Grand Bank common stock exchanged in the merger.

For further information, please refer to “Proposal to Approve the Reorganization Agreement—Material U.S. Federal Income Tax Consequences of the Merger.” The U.S. federal income tax consequences described above may not apply to all holders of Grand Bank common stock. Your tax consequences will depend on your individual situation. Accordingly, we strongly urge you to consult your tax advisor for a full understanding of the particular tax consequences of the merger to you.

Fairness Opinion of Grand Bank’s Financial Advisor (page 47)

Hovde Group, LLC, or Hovde Group, has delivered a written opinion to the board of directors of Grand Bank that, as of the date of the reorganization agreement, based upon and subject to certain matters stated in the opinion, the merger consideration is fair to the shareholders of Grand Bank from a financial point of view. This opinion is attached to this proxy statement/prospectus as Appendix B. The opinion of Hovde Group is not a recommendation to any Grand Bank shareholder as to how to vote on the proposal to approve the reorganization agreement. You should read this opinion completely to understand the procedures followed, matters considered and limitations on the reviews undertaken by Hovde Group in providing its opinion.

Independent Plans to Continue Payment of Quarterly Dividends (page 88)

Independent has paid cash dividends on its common stock since the third quarter of 2013, and, subject to applicable statutory and regulatory restrictions, intends to continue to pay quarterly cash dividends on its common stock following the merger. See “Dividends.”

Ownership of Independent Common Stock After the Merger (page 78)

Based on the closing price of Independent common stock on September 22, 2015, of $39.49 per share, Independent would issue 1,279,532 shares of its common stock to Grand Bank shareholders in connection with the merger. The number of shares of Independent common stock issued in connection with the merger is subject to change if the average sales price of the Independent common stock is less than $39.3894 or more than $48.1426. See “Summary—Terms of the Merger.”

Based on 17,111,394 shares of Independent common stock outstanding and the closing price of $39.49 on September 22, 2015, immediately after the merger, the former Grand Bank shareholders would own approximately 6.96% of the outstanding shares of Independent common stock assuming 1,279,532 shares of Independent common stock are issued in the merger. That ownership percentage would be reduced by any future issuances of shares of Independent common stock.

Market Prices of Independent Common Stock (page 88)

Shares of Independent common stock are quoted on the NASDAQ Global Select Market under the symbol “IBTX.” On July 22, 2015, the last trading day before the merger was announced, Independent common stock closed at $44.65 per share. On September 22, 2015, Independent common stock closed at $39.49 per share. The market price of Independent common stock will fluctuate prior to the merger. You should obtain the most recent closing price for Independent common stock on the NASDAQ Global Select Market prior to deciding how to vote. Shares of the common stock of Grand Bank are not traded on any national securities exchange or on an established public trading market, and no quotations of any market price exists for the Grand Bank shares of common stock.

Special Meeting (page 35)

The special meeting of shareholders of Grand Bank will be held on October 27, 2015, at 1:30 p.m., Central Time, at the main office of Grand Bank, 16660 Dallas Parkway, Suite 1700, Dallas, Texas 75248. At the special meeting, you will be asked to consider and vote on the following:

Record Date Set at September 18, 2015; Two-Thirds Shareholder Vote Required to Approve the Reorganization Agreement (pages 36 and 37)

You may vote at the special meeting of Grand Bank shareholders if you owned Grand Bank common stock of record as of 5:00 p.m. on September 18, 2015. You can cast one vote for each share of Grand Bank common stock you owned of record at that time. As of the record date, there were 1,726,810 shares of Grand Bank common stock outstanding.

Approval of the reorganization agreement requires the affirmative vote of the holders of at least two-thirds of the shares of Grand Bank common stock outstanding and entitled to vote as of 5:00 p.m. on the record date. If you fail to vote, it will have the effect of a vote against the reorganization agreement. The affirmative vote of the holders of a majority of the shares of Grand Bank common stock cast at the special meeting is required to approve the adjournment of the special meeting.

You may vote your shares of Grand Bank common stock by attending the special meeting and voting in person or by completing and mailing the enclosed proxy card. If you are the record holder of your shares, you can revoke your proxy at any time before the vote is taken at the special meeting by sending a written notice revoking the proxy or submitting a later-dated proxy to the Secretary of Grand Bank, which must be received no later than immediately prior to the vote at the special meeting, or by voting in person at the special meeting. See “The Special Meeting” beginning on page 35.

Recommendation of Grand Bank Board and Its Reasons for the Merger (page 35)

Based on the reasons discussed elsewhere in this proxy statement/prospectus, including the fairness opinion of Hovde Group, the board of directors of Grand Bank believes that the merger is fair to you and in your best interests, and unanimously recommends that you vote FOR the proposal to approve the reorganization agreement and the merger. For a discussion of the circumstances surrounding the merger and the factors considered by Grand Bank’s board of directors in approving the reorganization agreement, see page 46.

Certain Shareholders of Grand Bank are Expected to Vote Their Shares For Approval of the Reorganization Agreement (page 74; Exhibit A to Appendix A)

The directors of Grand Bank have entered into an agreement to vote the shares of Grand Bank common stock that they control in favor of approval of the reorganization agreement. As of the record date, 509,223 shares of Grand Bank common stock, or approximately 29% of the outstanding shares of Grand Bank common stock entitled to vote at the special meeting, were bound by the voting agreement.

Effective Time of the Merger (page 59)

The merger of Grand Bank with and into Independent Bank will become effective at the date and time specified in the certificate of merger to be filed with the Texas Department of Banking, or the TDB. If Grand Bank shareholders approve the reorganization agreement at the special meeting, and if all necessary regulatory approvals are obtained and the other conditions to the parties’ respective obligations to effect the merger are satisfied or are waived by the party entitled to do so, Independent anticipates that the merger will be completed in the late fourth quarter of 2015, although delays could occur.

Grand Bank and Independent cannot assure you that the necessary shareholder and regulatory approvals will be obtained or that the other conditions to completion of the merger can or will be satisfied. See “Risk Factors—The merger may not be completed” on page  28.

Exchange of Grand Bank Stock Certificates (page 58)

Approximately twenty days prior to closing, you will receive a letter and instructions from Wells Fargo Shareowner Services, acting in its role as Independent’s exchange agent and stock transfer agent, or the exchange agent, describing the procedures for surrendering your stock certificates representing shares of Grand Bank common stock in exchange for shares of Independent common stock and cash. If you surrender your certificate representing shares of Grand Bank common stock and properly completed transmittal materials at least two days prior to closing, then Independent will use its best efforts to cause the exchange agent to mail the merger consideration to you within five business days following the effective time of the merger. If you surrender your certificates and transmittal materials after two business day prior to closing, Independent will use its best efforts to cause the exchange agent to deliver the merger consideration to you promptly, with the intent that the exchange agent will mail the merger consideration to you within ten business days following receipt of the surrendered certificates and transmittal materials. You must carefully review and complete these transmittal materials and return them as instructed along with your stock certificates for Grand Bank common stock. Please do not send Grand Bank or Independent any stock certificates for your shares of Grand Bank common stock until you receive these instructions. Share certificates delivered to the exchange agent without a properly completed letter of transmittal will be rejected and returned for corrective action.

The shares of Independent common stock issuable in exchange for the shares of Grand Bank common stock will be issued solely in uncertificated book-entry form and a holder’s shares of Independent common stock will be reflected in the shareholder’s account established in the Direct Registration System of the Depositary Trust Company, or DTC, by Independent’s stock transfer agent. You will receive a statement to this effect from the transfer agent as part of the delivery of the merger consideration. You may then contact your broker and arrange for the transfer of shares to your brokerage account should you desire to do so.

Conditions to Completion of the Merger (page 64)

The completion of the merger depends on a number of conditions being satisfied. These include, among others:

Additionally, the completion of the merger depends on the execution of the following agreements, but those agreements will not become effective until the effective time of the merger:

Any condition to the completion of the merger, other than the required shareholder and regulatory approvals and the absence of an order prohibiting the merger, may be waived in writing by the party to the reorganization agreement entitled to the benefit of such condition. A party to the reorganization agreement could choose to complete the merger even though a condition has not been satisfied, as long as permitted by law. Independent cannot be certain when or if the conditions to the merger will be satisfied or waived, or that the merger will be completed.

Regulatory Approvals Required for the Merger (page 79)

The acquisition of Grand Bank by Independent requires the approval of the Board of Governors of the Federal Reserve System, or the Federal Reserve. In addition, the merger requires the approval of the Federal Deposit Insurance Corporation, or the FDIC, and the TDB. On August 27, 2015, Independent, Independent Bank and Grand Bank filed applications with the Federal Reserve, the FDIC and the TDB to obtain approval of the transaction. Independent expects to obtain all necessary regulatory approvals, although Independent cannot be certain if or when Independent will obtain them.

Amendments or Waiver of the Reorganization Agreement (page 71)

Independent and Grand Bank may amend the reorganization agreement and each party may waive its right to require the other party to adhere to any term or satisfy any condition of the reorganization agreement. However, the merger consideration to be received by the shareholders of Grand Bank pursuant to the terms of the reorganization agreement may not be decreased after the approval of the reorganization agreement without the further approval of the Grand Bank shareholders.

No Solicitation (page 63)

Pursuant to the reorganization agreement, Grand Bank has agreed that it will not, and that it will cause its employees, directors, officers, financial advisors or agents not to, solicit, knowingly encourage, initiate or participate in any negotiations or discussions with any third party regarding an acquisition proposal, disclose to any third party any information concerning its business, properties, books or records in connection with any acquisition proposal, or cooperate with any third party to make any acquisition proposal. Grand Bank has also agreed that, promptly upon receipt of any unsolicited offer, it will communicate to Independent the terms of any proposal or request for information and the identity of the parties involved.

Provided that Grand Bank has complied with the foregoing restrictions, if prior to obtaining shareholder approval of the merger, Grand Bank receives a bona fide, unsolicited written acquisition proposal, it may engage in negotiations and discussions with, and furnish any information and other access to, any person making such acquisition proposal if, and only if, Grand Bank’s board of directors determines in good faith, after consultation with outside legal and financial advisors, that such acquisition proposal is or is reasonably capable of becoming a superior offer to the merger with Independent Bank and the failure of Grand Bank’s board of directors to furnish such information or access or enter into such discussions or negotiations would reasonably be expected to be a violation of its fiduciary duties to the shareholders of Grand Bank; provided further that Grand Bank obtains an appropriately executed confidentiality agreement from the person making the acquisition proposal before furnishing any material nonpublic information to that person.

Termination of the Reorganization Agreement (page 71)

Independent and Grand Bank can mutually agree at any time to terminate the reorganization agreement without completing the merger. In addition, either Independent or Grand Bank may decide, without the consent of the other, to terminate the reorganization agreement if:

Grand Bank may terminate the reorganization agreement, without the consent of Independent, if:

In addition, Independent may terminate the reorganization agreement, without the consent of Grand Bank, if:

Termination Fee (page 72)

To compensate Independent for entering into the reorganization agreement, taking actions to consummate the transactions contemplated by the reorganization agreement and incurring the related costs and expenses and other losses and expense, including foregoing the pursuit of other opportunities, Grand Bank has agreed to pay Independent a $2.8 million termination fee, provided that Independent is not in material breach of any covenant or obligation under the reorganization agreement, if the reorganization agreement is terminated:

Financial Interests of Directors and Executive Officers of Grand Bank in the Merger (page 73)

Some of the directors and executive officers of Grand Bank have interests in the merger that differ from, or are in addition to, their interests as shareholders of Grand Bank. These interests include:

Comparison of Rights of Shareholders of Grand Bank and Independent (page 97)

Grand Bank is a Texas banking association, and the rights of shareholders of Grand Bank are governed by Texas law and Grand Bank’s articles of association and bylaws. Independent is a Texas corporation that is a registered bank holding company, and the rights of Independent’s shareholders are governed by Texas law and Independent’s certificate of formation and bylaws. Upon completion of the merger, shareholders of Grand Bank will become shareholders of Independent and their rights as shareholders of Independent will be governed by Independent’s certificate of formation and bylaws, in addition to Texas law. Independent’s certificate of formation and bylaws will not be amended in the merger, but could be later restated, amended or, as regards the bylaws, repealed.

Dissenters’ Rights of Grand Bank Shareholders (page 79)

As a holder of Grand Bank common stock, you have the right under Texas law to dissent from the merger and have the appraised fair value of your shares of Grand Bank common stock as of the date immediately preceding the effective date of the merger paid to you in cash. The appraised fair value may be more or less than the value of the shares of Independent common stock and cash shareholders of Grand Bank will receive for their Grand Bank shares in the merger.

In order to dissent, you must carefully follow the requirements of the TBOC, including providing Grand Bank, prior to the special meeting, with a written objection to the merger that states that you will exercise your right to dissent if the Grand Bank shareholders approve the reorganization agreement and the merger is completed. These steps for perfecting your right of dissent are summarized under the caption “—Dissenters’ Rights of Grand Bank Shareholders” on page 79. The provisions of the TBOC pertaining to dissenters’ rights are attached to this proxy statement/prospectus as Appendix C and the summaries of those provisions in this proxy statement/prospectus should be read in conjunction with, and are qualified by, those provisions of the TBOC.

If you intend to exercise dissenters’ rights, you should read the provisions of the TBOC governing dissenters’ rights carefully and consult with your own legal counsel. You should also remember that if you return

a signed proxy card, but fail to provide instructions as to how your shares of Grand Bank common stock are to be voted, you will be considered to have voted in favor of the reorganization agreement. In that event, you will not be able to assert dissenters’ rights.

If the Grand Bank shareholders approve the reorganization agreement, a holder of Grand Bank common stock who delivers to the president and the secretary of Grand Bank a written objection to the merger prior to the special meeting that states that such holder will exercise his or her right to dissent if the reorganization agreement is approved and the merger is completed and includes an address for notice of the effectiveness of the merger, who votes his or her shares of Grand Bank common stock against approval of the reorganization agreement at the special meeting, who, not later than the 20^th day after Independent sends such holder notice that the merger was completed, delivers to the president and secretary of Independent a written demand for payment of the fair value of his or her shares of Grand Bank common stock that states the number and class of shares of Grand Bank common stock such holder owns, his or her estimate of the fair value of such stock and an address to which a notice relating to the dissent and appraisal procedures may be sent, and who, not later than the 20^th day after he or she makes that demand for payment, submits to Independent the certificates representing his or her shares of Grand Bank common stock will be entitled under the TBOC to receive the appraised fair value of his or her shares of Grand Bank common stock, as of the date immediately prior to the effective time of the merger, in cash under the TBOC.

Selected Financial Information of Independent

The following selected historical consolidated financial information of Independent as of and for the six months ended June 30, 2015 and 2014 has been derived from Independent’s unaudited consolidated financial statements as of June 30, 2015, and for the six months ended June 30, 2015 and 2014, incorporated by reference in this proxy statement/prospectus. The following selected consolidated financial information of Independent as of June 30, 2014, has been derived from Independent’s unaudited consolidated financial statements not incorporated by reference in this proxy statement/prospectus. The following selected consolidated financial information of Independent as of December 31, 2014 and 2013, and for the years ended December 31, 2014, 2013 and 2012, has been derived from Independent’s audited consolidated financial statements incorporated by reference in this proxy statement/prospectus. The selected consolidated financial information as of December 31, 2012, 2011 and 2010, and for the years ended December 31, 2011 and 2010, has been derived from Independent’s audited consolidated financial statements not incorporated by reference in this proxy statement/prospectus.

You should read the following financial information relating to Independent in conjunction with other information contained in this proxy statement/prospectus, including consolidated financial statements of Independent and related accompanying notes incorporated by reference in this proxy statement/prospectus. Independent’s historical results for any prior period are not necessarily indicative of results to be expected in any future period, and Independent’s historical results for the six months ended June 30, 2015, are not necessarily indicative of its results to be expected for all of 2015. Independent has consummated several acquisitions in recent fiscal periods. The results and other financial information of those acquired operations are not included in the table below for the periods or dates prior to their respective acquisition dates and, therefore, the results for these prior periods are not comparable in all respects and may not be predictive of Independent’s future results. In addition, the selected financial information in the table immediately below does not include, on any basis, the results or financial condition for any period or as of any date of Grand Bank or of any other entity the acquisition of which may be consummated by Independent after June 30, 2015.

Independent believes that the presentation of tangible common equity to tangible assets provides useful information to investors regarding Independent’s financial condition because, as do Independent’s management, banking regulators, many financial analysts and other investors, you can use the tangible common equity in conjunction with more traditional bank capital ratios to assess Independent’s capital adequacy without the effect of Independent’s goodwill and core deposit intangibles and compare Independent’s capital adequacy with the capital adequacy of other banking organizations with significant amounts of goodwill and/or core deposit intangibles. A reconciliation of the ratios of tangible common equity to tangible assets to the ratios of total stockholders’ equity to total assets is presented below.

Reconciliations of Non-GAAP Financial Measures

The following information reconciles: (i) Independent’s tangible book value per common share, a non-GAAP financial measure, as of the dates presented to Independent’s book value per common share, a financial measure calculated and presented in accordance with GAAP, as of the dates presented; and (ii) our ratio of tangible common equity to tangible assets, a non-GAAP financial measure, as of the dates presented to Independent’s ratios of total stockholders’ equity to total assets, a financial measure calculated and presented in accordance with GAAP, as of the dates presented.

Selected Financial Information of Grand Bank

The following selected historical financial information of Grand Bank for the capital ratios described below as of and for the six months ended June 30, 2015 and 2014 has been derived from Grand Bank’s unaudited financial statements as of and for the six months ended June 30, 2015 and 2014, which Grand Bank’s management believes reflect all adjustments (consisting only of normal recurring adjustments) necessary for a fair presentation of its financial position and results of operations as of and for the periods ended on such dates. The following selected historical financial information of Grand Bank as of and for each of the five years ended December 31, 2014, has been derived from Grand Bank’s audited financial statements. Grand Bank’s historical results for any prior period are not necessarily indicative of results to be expected in any future period, and Grand Bank’s historical results for the six months ended June 30, 2015, are not necessarily indicative of its results to be expected for all of 2015. Consistent with the rules of the SEC, Grand Bank’s financial statements are not presented in this proxy statement/prospectus.

Grand Bank’s management believes that presenting tangible book value per share provides useful information to investors regarding Grand Bank’s financial condition because, as do Grand Bank’s management, banking regulators, many financial analysts and other investors, you can use tangible book value in conjunction with more traditional bank capital ratios to assess Grand Bank’s capital adequacy without the effect of goodwill and other intangible assets, and to compare Grand Bank’s capital adequacy with that of other banking organizations with significant amounts of goodwill and/or other intangible assets, which typically result from the use of the purchase method of accounting for mergers and acquisitions.

The following table presents, as of the dates set forth below, Grand Bank’s total assets, tangible assets, total stockholders’ equity and tangible common equity and presents reconciliations of Grand Bank’s tangible book value per common share to its book value per common share and of its ratio of tangible common equity to tangible assets to its ratio of total stockholders’ equity to total assets: