26 USC 7528 - Internal Revenue Service user fees

(a) General rule 
The Secretary shall establish a program requiring the payment of user fees for
(1) requests to the Internal Revenue Service for ruling letters, opinion letters, and determination letters, and
(2) other similar requests.
(b) Program criteria 

(1) In general 
The fees charged under the program required by subsection (a)
(A) shall vary according to categories (or subcategories) established by the Secretary,
(B) shall be determined after taking into account the average time for (and difficulty of) complying with requests in each category (and subcategory), and
(C) shall be payable in advance.
(2) Exemptions, etc. 

(A) In general 
The Secretary shall provide for such exemptions (and reduced fees) under such program as the Secretary determines to be appropriate.
(B) Exemption for certain requests regarding pension plans 
The Secretary shall not require payment of user fees under such program for requests for determination letters with respect to the qualified status of a pension benefit plan maintained solely by 1 or more eligible employers or any trust which is part of the plan. The preceding sentence shall not apply to any request
(i) made after the later of
(I) the fifth plan year the pension benefit plan is in existence, or
(II) the end of any remedial amendment period with respect to the plan beginning within the first 5 plan years, or
(ii) made by the sponsor of any prototype or similar plan which the sponsor intends to market to participating employers.
(C) Definitions and special rules 
For purposes of subparagraph (B)
(i) Pension benefit plan The term pension benefit plan means a pension, profit-sharing, stock bonus, annuity, or employee stock ownership plan.
(ii) Eligible employer The term eligible employer means an eligible employer (as defined in section 408 (p)(2)(C)(i)(I)) which has at least 1 employee who is not a highly compensated employee (as defined in section 414 (q)) and is participating in the plan. The determination of whether an employer is an eligible employer under subparagraph (B) shall be made as of the date of the request described in such subparagraph.
(iii) Determination of average fees charged For purposes of any determination of average fees charged, any request to which subparagraph (B) applies shall not be taken into account.
(3) Average fee requirement 
The average fee charged under the program required by subsection (a) shall not be less than the amount determined under the following table: