AGREEMENT AND PLAN OF MERGER

Exhibit 99.1

AGREEMENT AND PLAN OF MERGER

by and among

CENTERSTATE BANKS OF FLORIDA, INC.

CENTERSTATE BANK MID FLORIDA

ATLANTIC SOUTHERN FINANCIAL GROUP, INC.

and

ATLANTIC SOUTHERN BANK

Dated as of August 10, 2007

TABLE OF CONTENTS

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AGREEMENT AND PLAN OF MERGER

This AGREEMENT AND PLAN OF MERGER (this “Agreement”) is made and entered into as of the 10th day of August 2007, by and among ATLANTIC SOUTHERN FINANCIAL GROUP, INC., a Georgia corporation (“ASFG”), ATLANTIC SOUTHERN BANK, a Georgia state bank and wholly-owned subsidiary of ASFG (“ASB”), CENTERSTATE BANKS OF FLORIDA, INC., a Florida corporation (“CSB”) and CENTERSTATE BANK MID FLORIDA, a Florida state bank and wholly-owned subsidiary of CSB (“Target”).

WITNESSETH :

WHEREAS, ASB is a Georgia state bank with its principal offices in Macon, Georgia, and is a wholly-owned subsidiary of ASFG;

WHEREAS, the Target is a Florida state bank located in Lake County, Florida and is a wholly-owned subsidiary of CSB;

WHEREAS, the respective Boards of Directors of ASFG, ASB, CSB and the Target are of the opinion that the transactions described herein are in the best interests of the parties to this Agreement and their respective shareholders; and

WHEREAS, this Agreement provides for the merger of Target with and into ASB (the “Merger”), with ASB being the surviving bank (as a Georgia state bank);

NOW, THEREFORE, for and in consideration of the foregoing and of the mutual representations, warranties, covenants and agreements contained in this Agreement, and other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, and subject to the conditions set forth below, the parties, intending to be legally bound, undertake, promise, covenant and agree with each other as follows:

ARTICLE I.

TRANSACTION

Section 1.01 Merger . Subject to the terms and conditions of this Agreement, Target shall be merged with and into ASB with the effect provided in Section 7-1-536 of the Financial Institutions Code of Georgia (“FICG”) and Section 658.2953 of the Financial Institutions Code of Florida. ASB shall be the Surviving Entity resulting from the Merger and shall continue to be governed by the Laws of the State of Georgia. The Merger shall be consummated pursuant to the terms of this Agreement, which has been approved and adopted by the respective Boards of Directors of CSB, Target, Atlantic Southern and ASB.

Section 1.02 Effective Time . The Merger and other transactions contemplated by this Agreement shall become effective on the date and at the time the Certificate of Merger reflecting the Merger shall become effective with the Secretary of State of Georgia and the Secretary of State of Florida (the “Effective Time”). At the Effective Time, the separate corporate existence of Target shall cease, and ASB shall continue as the Surviving Entity.

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ARTICLE II.

TERMS OF MERGER

Section 2.01 Articles of Incorporation . The Articles of Incorporation of ASB in effect immediately prior to the Effective Time shall be the Articles of Incorporation of the Surviving Entity until otherwise duly amended or repealed.

Section 2.02 Bylaws . The Bylaws of ASB in effect immediately prior to the Effective Time shall be the Bylaws of the Surviving Entity until duly amended or repealed.

Section 2.03 Merger Consideration . As consideration for the Merger, ASB shall pay CSB in immediately available funds, an amount equal to the sum of $1,000,000, less the Deposit received by CSB pursuant to Section 4.04, plus an amount equal to the aggregate capital accounts (the “Merger Consideration”) at the Closing. All Target capital accounts shall be disclosed in Section 2.03 of the Target Disclosure Memorandum .

Section 2.04 Closing and Closing Date . Following the receipt of all necessary regulatory, corporate and other approvals necessary for the consummation of the transactions contemplated in this Agreement (as required by Section 3.03, Section 3.05 and Section 4.03 of this Agreement) and the expiration of any mandatory waiting periods, the Merger provided for in this Agreement shall be consummated at a closing (the “Closing”) to be held on November 30, 2007 (the “Closing Date”).

ARTICLE III.

CONDITIONS PRECEDENT TO OBLIGATIONS OF ASFG AND ASB

All obligations of ASFG and ASB are subject to the fulfillment, prior to or at the Closing, of each of the following conditions, any or all of which may be waived in whole or in part by ASFG or ASB.

Section 3.01 Compliance with Representations Warranties and Agreements . All representations and warranties made by CSB and the Target in this Agreement shall have been true and correct in all material respects when made and shall be true and correct in all material respects as of the Closing with the same force and effect as if such representations and warranties were made at and as of the Closing. CSB and the Target shall have performed or complied in all material respects with all agreements, terms, covenants and conditions required by this Agreement to be performed or complied with by CSB and the Target prior to or at the Closing.

Section 3.02 Proceedings and Documents . All actions, proceedings, instruments and documents required to effectuate this Agreement or incidental hereto shall be satisfactory in substance and form to ASFG and ASB, and ASB shall have received all such counterpart originals or certified or other copies of such documents as it may reasonably request, including certified copies of all resolutions authorizing this Agreement and the transactions contemplated herein.

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Section 3.03 Governmental and Regulatory Approvals . ASB and ASFG, on the one hand, and CSB and the Target, on the other hand, shall have obtained all governmental and regulatory approvals and consents necessary for the consummation of the Merger and the Related Transactions described in this Agreement. Such approvals include, without limitation, the approval of (i) the Board of Governors of the Federal Reserve System (the “Federal Reserve”), (ii) the FDIC, and (iii) the Georgia Department of Banking and Finance (the “GDBF”). No such approval or consent shall be conditioned or restricted in a manner which in the reasonable judgment of ASB or ASFG would unduly impair or restrict the operations of the Target, ASB or ASFG following the Closing or render consummation of the Merger and the Related Transactions unduly burdensome; provided that ASB and ASFG have used their reasonable efforts (it being understood that such reasonable efforts shall not include the threatening or commencement of any litigation) to cause such conditions or restrictions to be removed or modified as appropriate.

Section 3.04 No Litigation . No action shall have been taken, and no statute, rule, regulation or order shall have been promulgated, enacted, entered, enforced or deemed applicable to this Agreement or the transactions contemplated hereby by any governmental authority or by any court, including the entry of a preliminary or permanent injunction, that would (a) make this Agreement or the transactions contemplated hereby illegal, invalid or unenforceable, (b) require the divestiture of a material portion of the assets of ASB or the Target, (c) impose material limits in the ability of any party to this Agreement to consummate the Agreement or the transactions contemplated hereby, or (d) if this Agreement or the transactions contemplated hereby are consummated, subject ASFG, ASB or any officer, director, shareholder or employee of ASFG or ASB to criminal or civil liability. No action or proceeding before any court or governmental authority shall be threatened, instituted or pending that would reasonably be expected to result in any of the consequences referred to in clauses (a) through (d) above.

Section 3.05 Related Transactions . Prior to the Closing, CenterState Bank West Florida (“CBWF”) will acquire all of the assets and all of the banking offices of the Target, except for the main office of the Target (the “Main Office”) and the amount of deposits required by the FDIC to maintain the required depository insurance (which deposits ASB will cause to be placed in Target prior to the Closing). Immediately subsequent to the Closing, ASB will transfer the Main Office to CBWF. ASB will have received, prior to the Effective Time, permission from the FDIC and the GBDF to establish a branch in the state of Florida at a location to be determined by ASB, which branch will open for business as of the Effective Time. The transactions described in this Section 3.05 are the “Related Transactions.”

Section 3.06 Retained Assets; No Deposits or Other Liabilities . The assets of the Target immediately subsequent to the Closing Date and upon consummation of the ASB Main Office transfer to CBWF, shall consist of the Target’s charter, articles, bylaws, and cash equal to the capital accounts of the Target and to the amount of deposits required by the FDIC to maintain the required depository insurance (the “Retained Assets”). On the Closing Date, the Target shall have no deposits or other liabilities outside of the deposits required by the FDIC to maintain the required depository insurance. The parties agree that the Retained Assets shall not include any rights to the name “CenterState Banks” or any variation thereof.

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Section 3.07 Third Party Consents . The Target shall receive all third party consents that may be necessary to consummate the Merger, effect the Related Transactions and transfer the contracts, leases, assets and obligations to CBWF.

Section 3.08 Actions to be Taken at the Closing by the CSB and the Target . At the Closing, CSB and the Target shall execute and acknowledge (as appropriate) and deliver to ASB and ASFG such documents and certificates necessary to carry out the terms and provisions of this Agreement, including the following (all of such actions constituting conditions precedent to ASB’s obligations to consummate hereunder):

A. A certificate, dated as of the Closing Date, executed by the appropriate officers of each of CSB and the Target, pursuant to which CSB and the Target shall certify that (i) all of the representations and warranties made by CSB and the Target in this Agreement are true and correct in all material respects on and as of the Closing Date as if made on such date and (ii) CSB and the Target has performed and is in compliance in all materials respects with all of CSB’s and the Target’s covenants and agreements contained herein.

B. A certificate, dated as of the Closing Date, duly executed by the Secretary or an Assistant Secretary of CSB and Target, acting solely in his or her capacity as an officer of CSB or the Target, as applicable, pursuant to which CSB and the Target shall certify (i) the due adoption by the Board of Directors of each of CSB and the Target of corporate resolutions attached to such certificate authorizing the execution and delivery of this Agreement and the other agreements and documents contemplated hereby, and the taking of all actions contemplated hereby and thereby; (ii) the incumbency and true signatures of those officers of CSB and the Target duly authorized to act on their behalf in connection with the transactions contemplated by this Agreement and to execute and deliver this Agreement and other agreements and documents contemplated hereby, and the taking of all actions contemplated hereby and thereby on behalf of CSB and the Target; and (iii) that the copy of the Bylaws of each of CSB and the Target attached to such certificate is true and correct and such Bylaws have not been amended except as reflected in such copy.

C. True, correct and complete copies of the Articles of Incorporation and other charter documents of the Target and all amendments thereto, duly certified as of a recent date by the Florida Secretary of State.

D. A Certificate of good standing for the Target, dated as of a recent date, issued by the Florida Secretary of State duly certifying to the good standing of the Target in the State of Florida.

E. The written resignation of all executive officers and directors of the Target. Effective as of the Closing, and the employment of all employees of the Target shall be terminated by the Target or CSB.

F. The written consent action of the sole shareholder of Target approving the Merger.

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G. All other documents required to be delivered to ASFG and ASB by CSB and the Target under the provisions of this Agreement and all other documents, certificates and instruments as are reasonably required by ASFG and ASB.

Section 3.09 Further Assurances . At any time and from time to time after the Closing, at the request of any party to this Agreement and without further consideration, any party so requested shall execute and deliver such other instruments and take such other actions as the requesting party may reasonably deem necessary or desirable in order to effect the transactions contemplated hereby.

ARTICLE V.

CONDITIONS PRECEDENT TO OBLIGATIONS OF CSB AND THE TARGET

All obligations of CSB and the Target under this Agreement are subject to the fulfillment, prior to or at the Closing, of each of the following conditions, any or all of which may be waived in whole or in part by CSB and the Target:

Section 4.01 Compliance with Representations, Warranties and Agreements . All representations and warranties made by ASFG and ASB in this Agreement shall have been true and correct in all material respects when made and shall be true and correct in all material respects as of the Closing with the same force and effect as if such representations and warranties were made at and as of the Closing. ASFG and ASB shall have performed or complied in all material respects with all agreements, terms, covenants and conditions required by this Agreement to be performed or complied with by ASFG or ASB prior to or at the Closing.

Section 4.02 Proceedings and Documents . All actions, proceedings, instruments and documents required to effectuate this Agreement or incidental hereto shall be reasonably satisfactory in substance and form to CSB and Target, and CSB and Target shall have received all such counterpart originals or certified or other copies of such documents as they may reasonably request, including certified copies of all resolutions authorizing this Agreement and the transactions contemplated herein.

Section 4.03 Governmental and Regulatory Approvals . ASFG and ASB on one hand, and CSB and the Target on the other hand, shall have obtained all governmental and regulatory approvals and consents necessary for the consummation of the Merger and the Related Transactions described in this Agreement and Target’s payment of a special dividend to CSB immediately prior to the Closing. Such approvals include, without limitation, the approval of (i) the Federal Reserve, (ii) the FDIC, and (iii) the GDBF. No such approval or consent shall be conditioned or restricted in a manner which in the reasonable judgment of Target or CSB would unduly impair or restrict the operations of ASB following the Closing or render consummation of the Merger and the Related Transactions unduly burdensome; provided that Target and CSB have used their reasonable efforts (it being understood that such reasonable efforts shall not include the threatening or commencement of any litigation) to cause such conditions or restrictions to be removed or modified as appropriate.

Section 4.04 Definitive Agreement Deposit . Upon execution of this Agreement, ASB shall pay to CSB, in immediately available funds, the sum of $100,000 (the “Deposit”). Such

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payment will be reduced from the Merger Consideration set forth in Section 2.03 provided the Merger is consummated. If the Merger is not consummated, such payment shall be nonrefundable unless (i) ASB is ready and able to consummate the Merger, and CSB or the Target fail to consummate the Merger or effect the Related Transactions described in Section 3.05, or (ii) ASB is unable to acquire all necessary regulatory approvals or may acquire said approvals only upon a condition or conditions contemplated by the last sentence of Section 4.03 of this Agreement.

Section 4.05 No Litigation . No action shall have been taken, and no statute, rule, regulation or order shall have been promulgated, enacted, entered, enforced or deemed applicable to this Agreement or the transactions contemplated hereby by any governmental authority or by any court, including the entry of a preliminary or permanent injunction, that would (a) make this Agreement or the transactions contemplated hereby illegal, invalid or unenforceable, (b) impose material limits in the ability of any party to this Agreement to consummate the Agreement or the transactions contemplated hereby, or (c) if this Agreement or the transactions contemplated hereby are consummated, subject CSB, the Target or any officer, director, shareholder or employee of CSB or the Target to criminal or civil liability. No action or proceeding before any court or governmental authority shall be threatened, instituted or pending that would reasonably be expected to result in any of the consequences referred to in clauses (a) through (c) above.

Section 4.06 Related Transactions . Prior to the Closing, CBWF will acquire all of the assets and all of the banking offices of the Target, except for the Main Office and the amount of deposits required by the FDIC to maintain the required depository insurance. Immediately subsequent to the Closing, ASB will transfer the Main Office to CBWF. ASB will have received, prior to the Effective Time, permission from the FDIC and the GBDF to establish a branch in the state of Florida at a location to be determined by ASB, which branch will open for business as of the Effective Time.

Section 4.07 Third Party Consents . The Target shall receive all third party consents that may be necessary to consummate the Merger and necessary for Target to transfer its contracts, leases, assets and obligations to CSB.

Section 4.08 Actions to be Taken at the Closing by ASFG and ASB . At the Closing, ASB and ASFG shall deliver to the Target the following:

A. Merger Consideration paid by one or more wire transfers.

B. A certificate, dated as of the Closing Date, executed by the appropriate officers of ASB and ASFG, pursuant to which ASB and ASFG shal