Solo 401(k) Contribution

§ 401. Qualified pension, profit-sharing, and stock bonus plans(a) Requirements for qualificationA trust created or organized in the United States and forming part of a stock bonus, pension, or profit-sharing plan of an employer for the exclusive benefit of his employees or their beneficiaries shall constitute a qualified trust under this section—(1) if contributions are made to the trust by such employer, or employees, or both, or by another employer who is entitled to deduct his contributions under section 404(a)(3)(B) (relating to deduction for contributions to profit-sharing and stock bonus plans), or by a charitable remainder trust pursuant to a qualified gratuitous transfer (as defined in section 664(g)(1)), for the purpose of distributing to such employees or their beneficiaries the corpus and income of the fund accumulated by the trust in accordance with such plan; (2) if under the trust instrument it is impossible, at any time prior to the satisfaction of all liabilities with respect to employees and their beneficiaries under the trust, for any part of the corpus or income to be (within the taxable year or thereafter) used for, or diverted to, purposes other than for the exclusive benefit of his employees or their beneficiaries (but this paragraph shall not be construed, in the case of a multiemployer plan, to prohibit the return of a contribution within 6 months after the plan administrator determines that the contribution was made by a mistake of fact or law (other than a mistake relating to whether the plan is described in section 401(a) or the trust which is part of such plan is exempt from taxation under section 501(a), or the return of any withdrawal liability payment determined to be an overpayment within 6 months of such determination)); (3) if the plan of which such trust is a part satisfies the requirements of section 410 (relating to minimum participation standards); and (4) if the contributions or benefits provided under the plan do not discriminate in favor of highly compensated employees (within the meaning of section 414(q)). For purposes of this paragraph, there shall be excluded from consideration employees described in section 410(b)(3)(A) and (C). (5) Special rules relating to nondiscrimination requirements.—(A) Salaried or clerical employees.—A classification shall not be considered discriminatory within the meaning of paragraph (4) or section 410(b)(2)(A)(i) merely because it is limited to salaried or clerical employees. (B) Contributions and benefits may bear uniform relationship to compensation.—A plan shall not be considered discriminatory within the meaning of paragraph (4) merely because the contributions or benefits of, or on behalf of, the employees under the plan bear a uniform relationship to the compensation (within the meaning of section 414(s)) of such employees.