EXHIBIT 99

FASTENAL COMPANY STOCK OPTION PLAN

This Plan is adopted and made by Fastenal Company, a Minnesota corporation with principal offices at Winona, Minnesota (the “Company”), for the benefit of certain employees of the Company and its subsidiaries.

1. Purpose.

The Fastenal Company Stock Option Plan (the “Plan”) is intended to advance the interests of the Company, its shareholders, and its subsidiaries, by encouraging and enabling selected employees upon whose judgment, initiative and effort the Company and its subsidiaries are dependent for the successful conduct of their business, to acquire and retain a proprietary interest in the Company by ownership of its Shares. All Options granted under the Plan and all Shares sold upon exercise of Options are granted and sold by the Company. Options granted under the Plan will not be options that meet the requirements of Section 422 of the Internal Revenue Code of 1986 (the “Code”).

2. Definitions.

(a) “Administrator” means the body administering the Plan, as specified in Section 9.

(b) “Board” means the Board of Directors of the Company.

(c) “Company” means Fastenal Company, a Minnesota corporation, and any successor corporation.

(d) “Common Stock” means the Company’s $.01 par value Common Stock.

(e) “Date of Grant” means the date on which the Administrator approves the grant of an Option under the Plan.

(f) “Option” means an Option granted under the Plan.

(g) “Optionee” means a person to whom an Option, which has not expired, has been granted under the Plan.

(h) “Shares” shall mean shares of Common Stock, or such other securities or property as may become subject to Options pursuant to an adjustment as provided under Section 7 of the Plan.

(i) “Subsidiary” or “Subsidiaries” means a subsidiary corporation or corporations of the Company as defined in Section 424 of the Code.

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(j) “Successor” means the legal representative of the estate of a deceased Optionee or the person or persons who acquire the right to exercise an Option by bequest or inheritance or by reason of the death of any Optionee.

3. Shares Subject to Options.

The aggregate number of authorized and unissued Shares for which Options may be granted and which may be purchased upon the exercise of Options granted under the Plan shall not exceed 3,793,865¹, subject to adjustment under the provisions of paragraph 7. In the event any Option shall, for any reason, terminate or expire or be surrendered without having been exercised in full, other Options may be granted covering the Shares subject to the unexercised portion of such Option. The maximum number of Shares subject to Options that may be granted to any one individual under this Plan during any fiscal year of the Company (the “Maximum Annual Grant”) is 20,000 Shares², subject to adjustment under the provisions of paragraph 7.

4. Participants.

All employees of the Company and its Subsidiaries shall be eligible to participate in the Plan, subject to any criteria, categories, or limitations that may be established by the Administrator from time to time. Criteria for participation may reflect an employee’s contribution to the success of the Company, including the employee’s responsibility for Company revenues and profits, responsibility for managing other employees, possession of special skills, and length of service. The Administrator shall determine participation, grant Options, and specify the number of Shares subject to each Option.

5. Grant of Options.

Options shall be granted at such times as may be determined by the Administrator, as long as Shares remain available for award under the Plan, or until the Plan is terminated as provided herein.

6. Terms and Conditions of Options.

All Options granted under the Plan shall be evidenced by a written agreement or certificate in such form and with such terms as the Administrator may from time to time approve, subject to the following limitations and conditions:

(a) Option Price. The Option price per Share with respect to each Option shall be determined and stated by the Administrator at the time of grant. Such Option price shall be not less than the closing price at which Shares of the Common Stock were traded on the securities exchange or Nasdaq National Market System on which the Shares are then listed and traded on

¹ This number has been subsequently adjusted pursuant to the terms of the Plan to 7,587,730 to reflect the two-for-one stock split effected by the Company in November 2005.

² This number has been subsequently adjusted pursuant to the terms of the Plan to 40,000 to reflect the two-for-one stock split effected by the Company in November 2005.

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the most recent trading date preceding the date of grant. If the Common Stock is not then listed and traded upon a securities exchange or the Nasdaq National Market System, such Option price shall be not less than the fair market value of a Share on the date of grant, as determined by the Administrator. The determination of the Option price by the Administrator shall be binding upon the Optionee and all other persons.

(b) Period of Option. The expiration date with respect to each Option shall be determined and stated by the Administrator at the time of grant.

(c) Vesting of Shareholder Rights. Neither an Optionee nor any transferee pursuant to a Permitted Transfer (as defined below) shall have any of the rights of a shareholder of the Company until the Option has been exercised and the certificates evidencing the Shares purchased are properly delivered to such Optionee or transferee.

(d) Exercise of Option. The period during which each Option may be exercised shall be determined and stated by the Administrator in the award agreement or certificate at the time of grant. Except as otherwise provided in this Plan, an Option may be exercised only while the Optionee is employed by the Company or a Subsidiary, and only if the Optionee has been continuously so employed since the date the Option was granted.

(e) Manner of Exercise. Each exercise of an Option shall be in writing, in such form as the Administrator may prescribe, delivered to the Administrator or its designee, specifying the number of Shares being purchased and accompanied by payment of the Option price for such Shares, by check payable to the Company or in such other manner as the Administrator may prescribe.

(f) Nontransferability of Options. No Option shall be transferable or assignable by an Optionee, otherwise than by will or the laws of descent and distribution or pursuant to a domestic relations order as defined by the Code or Title I of the Employment Retirement Income Security Act (each a “Permitted Transfer”). Each Option shall be exercisable only by the Optionee or by a transferee pursuant to a Permitted Transfer. No Option shall be pledged or hypothecated in any way and no Option shall be subject to execution, attachment, or similar process.

(g) Termination of Employment. Except as otherwise provided in paragraph 6(h), upon termination of an Optionee’s employment with the Company or a Subsidiary, (i) any outstanding Option held by such Optionee shall terminate except to the extent that it is immediately exercisable by its terms at the date of such termination of employment and (ii) to the extent any such Option is immediately exercisable by its terms at the date of such termination of employment, it shall remain exercisable until the earlier of 90 days after the date of such termination of employment or the date of expiration of such Option. The granting of an Option to a Participant does not alter in any way the existing rights of the Company and its Subsidiaries to terminate such person’s employment at any time for any reason or for no reason, nor does it confer upon such person any rights or privileges except as specifically provided for in the Plan.

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(h) Death of Optionee. If an Optionee dies while in the employ of the Company or any Subsidiary, any outstanding Option shall be exercisable by the Optionee’s Successor during the same period and to the same extent as the option could have been exercised by the Optionee had the Optionee lived and remained employed by the Company or a Subsidiary.

7. Adjustments.

(a) Except as provided in paragraph 7(c), in the event of a capital adjustment resulting from a stock dividend, stock split, reorganization, merger, consolidation, or a combination or exchange of Shares, the number and kind of Shares subject to the Plan and the Maximum Annual Grant and the number and kind of Shares under each outstanding Option shall be adjusted consistent with such capital adjustment. The Option price of any Share under each outstanding Option shall be adjusted so that there will be no change in the aggregate purchase price payable upon exercise of any such Option. The granting of an Option pursuant to the Plan shall not affect in any way the right or power of the Company to make adjustments, reorganizations, reclassifications, or changes of its capital or business structure or to merge, consolidate, dissolve, liquidate, or sell or transfer all or any part of its business or assets.

(b) In the event of the dissolution or liquidation of the Company, any Option granted under the Plan shall terminate as of a date to be fixed by the Administrator, provided that not less than 30 days written notice of the date so fixed shall be given to each Optionee and each such Optionee shall have the right during such period (but in no event beyond the expiration date of the applicable Option) to exercise each of his outstanding Options as to all or any part of the Shares covered thereby including Shares as to which such Option would not otherwise be exercisable by reason of an insufficient lapse of time.

(c) In the event of a Reorganization (as hereinafter defined) in which the Company is not the surviving or acquiring company, or in which the Company is or becomes a wholly-owned subsidiary of another company after the effective date of the Reorganization, then

(1) If there is no plan or agreement respecting the Reorganization (“Reorganization Agreement”) or if the Reorganization Agreement does not specifically provide for the change, conversion, or exchange of the Shares under outstanding and unexercised Options for securities of another corporation, then any Option granted under the Plan shall terminate as of a date to be fixed by the Administrator, provided that not less than 30 days written notice of the date so fixed shall be given to each Optionee and each such Optionee shall have the right during such period (but in no event beyond the expiration date of the applicable Option) to exercise each of his outstanding Options as to all or any part of the Shares covered thereby including Shares as to which such Option would not otherwise be exercisable by reason of an insufficient lapse of time; or

(2) If there is a Reorganization Agreement and if the Reorganization Agreement specifically provides for the change, conversion, or exchange of the Shares under outstanding and unexercised Options for securities of another corporation, then the securities received on account of such Shares shall be subject to the Plan and then-outstanding Options. The Administrator may make appropriate adjustment in the

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number and kind of Shares for the purchase of which Options may be granted under the Plan and for the Maximum Annual Grant. In addition, the Administrator shall make appropriate adjustment in the number and kind of Shares as to which outstanding Options, or portions thereof then unexercised, shall be exercisable, to the end that the interest of the holder of the Option shall, to the extent practicable, be maintained as before the occurrence of such event. Such adjustment in outstanding Options shall be made without change in the total price applicable to the unexercised portion of the Option but with a corresponding adjustment in the Option price per Share.

The term “Reorganization” as used in this subparagraph (c) of this paragraph 7 shall mean any statutory merger, statutory consolidation, statutory share exchange, sale of all or substantially all of the assets of the Company, or sale, pursuant to an agreement with the Company, of securities of the Company pursuant to which the Company is or becomes a wholly-owned subsidiary of another company after the effective date of the Reorganization.

(d) Adjustments and determinations under this paragraph 7 shall be made by the Administrator, as specified herein, and its decisions as to what adjustments or determinations shall be made, and the extent thereof, shall be final, binding, and conclusive.

8. Restrictions on Issuing Shares.

The exercise of each Option and the issuance of Shares in connection therewith shall be subject to the condition that if at any time the Administrator shall determine in its discretion that the satisfaction of withholding tax or other withholding liabilities, or that the listing, registration, or qualification of any Shares otherwise deliverable upon such exercise upon any securities exchange or the Nasdaq National Market or under any state or federal law, or that the consent or approval of any regulatory body, is necessary or desirable as a condition of, or in connection with, such exercise or the delivery or purchase of Shares pursuant thereto, then in any such event, such exercise shall not be effective unless such withholding, listing, registration, qualification, consent, or approval shall have been effected or obtained free of any conditions not acceptable to the Administrator.

9. Administration of Plan.

The Plan shall be administered by the Board or by a committee of two or more directors of the Company appointed by the Board (the “Administrator”). If the Plan is administered by a committee, it shall report all action taken by it to the Board. In administering the Plan, the Administrator shall be governed by and shall adhere to the provisions of the Plan, including any criteria for eligibility or participation established by the Board from time to time. Subject to the foregoing, the Administrator shall determine eligibility to participate in the Plan, ascertain the number of Shares for which each participant is eligible in accordance with any established criteria, grant Options, construe and interpret the Plan, and make all other determinations and take all other actions deemed necessary or advisable for the proper administration of the Plan. All such actions and determinations shall be conclusively binding for all purposes and upon all persons. The Administrator may delegate administrative duties under this Plan to such officers or employees of the Company or others as it may determine.

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10. Delivery of Shares and Proceeds.

Upon the exercise of an Option, the Administrator shall cause a certificate for the purchased Shares to be issued by the Company’s transfer agent and delivered to the Optionee. The proceeds received from the sale of Shares pursuant to the exercise of Options granted under the Plan shall be the property of the Company, and shall be delivered to it promptly by the Administrator.

11. Amendment, Suspension, or Termination of Plan.

The Board may at any time suspend or terminate the Plan or may amend it from time to time in such respects as it may deem advisable in order that the Options granted thereunder may conform to any changes in the law or in any other respect which it may deem to be in the best interests of the Company. Unless the Plan shall theretofore have been terminated as provided herein, the Plan shall terminate when all available Shares have been granted and no granted Option is outstanding. No Option may be granted during any suspension or after the termination of the Plan. No amendment, suspension, or termination of the Plan shall, without an Optionee’s consent, impair any of the rights or obligations under any outstanding Option theretofore granted to such Optionee under the Plan. A Participant’s consent to any amendment, suspension, or termination of the Plan or to any Option issued pursuant to the Plan shall be deemed to have been given if the Participant fails to object in writing within 15 days after written notice thereof, given in person or by certified mail sent to the Participant’s address contained in the records of the Company. To the extent considered necessary to comply with applicable provisions of law or the listing requirements of any applicable securities exchange or the Nasdaq National Market, any such amendments to the Plan may be made subject to approval by the shareholders of the Company.

12. Adoption and Effective Date of Plan.

The Plan is approved and adopted by the Board of Directors on April 15, 2003. It will be submitted to the Shareholders of the Company at the next annual meeting. The Plan will be effective if approved by a majority of the outstanding Shares present and entitled to vote at such meeting, upon such approval or upon such other date as may be specified in the resolution of approval.

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