26 CFR §1.457-5

1. (a)General rule. The individual limitation under section 457(c) and this section equals the basic annual deferral limitation under § 1.457-4(c)(1)(i)(A), plus either the age 50 catch-up amount under § 1.457-4(c)(2), or the special section 457 catch-up amount under § 1.457-4(c)(3), applied by taking into account the combined annual deferral for the participant for any taxable year under all eligible plans. While an eligible plan may include provisions under which it will limit deferrals to meet the individual limitation under section 457(c) and this section, annual deferrals by a participant that exceed the individual limit under section 457(c) and this section (but do not exceed the limits under § 1.457-4(c)) will not cause a plan to lose its eligible status. However, to the extent the combined annual deferrals for a participant for any taxable year exceed the individual limitation under section 457(c) and this section for that year, the amounts are treated as excess deferrals as described in § 1.457-4(e).
2. (b)Limitation applied to participant. The individual limitation in this section applies to eligible plans of all employers for whom a participant has performed services, including both eligible governmental plans and eligible plans of a tax-exempt entity and both eligible plans of the employer and eligible plans of other employers. Thus, for purposes of determining the amount excluded from a participant's gross income in any taxable year (including the underutilized limitation under § 1.457-4 (c)(3)(ii)(B)), the participant's annual deferral under an eligible plan, and the participant's annual deferrals under all other eligible plans, must be determined on an aggregate basis. To the extent that the combined annual deferral amount exceeds the maximum deferral limitation applicable under § 1.457-4 (c)(1)(i)(A), (c)(2), or (c)(3), the amount is treated as an excess deferral under § 1.457-4(e).
3. (c)Special rules for catch-up amounts under multiple eligible plans. For purposes of applying section 457(c) and this section, the special section 457 catch-up under § 1.457-4 (c)(3) is taken into account only to the extent that an annual deferral is made for a participant under an eligible plan as a result of plan provisions permitted under § 1.457-4 (c)(3). In addition, if a participant has annual deferrals under more than one eligible plan and the applicable catch-up amount under § 1.457-4 (c)(2) or (3) is not the same for each such eligible plan for the taxable year, section 457(c) and this section are applied using the catch-up amount under whichever plan has the largest catch-up amount applicable to the participant.
4. (d)Examples. The provisions of this section are illustrated by the following examples: