Identify the 401(a) contribution sources before applying 415(c)
Begin with the plan document and payroll record, separating employee contributions, employer contributions, forfeitures allocated to the account, and additions under other plans of the same employer that must be aggregated. The ordinary IRC 415(c) annual-additions limit is not merely an employee deposit cap. A projection that ignores employer or related-plan amounts can show headroom that the plan administrator does not actually have.
For United States tax year 2025, the calculator uses a $70,000 415(c) dollar limit and a $350,000 regular IRC 401(a)(17) compensation cap. For 2026 it uses $72,000 and $360,000. The applicable additions ceiling is the lower of the selected year's dollar amount or 100% of recognized compensation. Selecting a year is therefore essential; the figures must never be presented as timeless plan rules.
When the plan actually includes employee elective deferrals and an employer match, compare that separate design with the 401(k) calculator instead of importing its 402(g) catch-up logic into every 401(a) arrangement.
Reconcile compensation caps and the governmental grandfather branch
Plan-defined compensation may differ from gross pay. Enter only the compensation basis supported by the plan and administrator. The separately confirmed grandfathered governmental-plan option uses a larger compensation cap—$520,000 for 2025 or $535,000 for 2026—but that branch is not a general public-employer setting. A user should not select it merely because the employer is governmental.
After capping eligible compensation, apply each declared contribution formula and add other annual additions. Compare that sum with both the dollar and compensation-based bounds, preserving full precision. A displayed excess is a screening signal for administrator review, not a correction instruction. Contribution timing affects the growth projection but does not change which additions belong in the statutory test for the year.
For a long-horizon accumulation scenario that is not a statutory additions screen, use the investment target calculator and keep its assumed return separate from the plan's current-year legal limit.
Keep 401(a), 401(k), pickup, and vesting questions distinct
An ordinary 401(a) contribution is not automatically an elective deferral governed by IRC 402(g), and the familiar 401(k) age-50 catch-up does not automatically attach. Some governmental plans use mandatory employee contributions, and an employer may treat qualifying contributions as picked up under IRC 414(h)(2). Those classifications depend on plan action and payroll facts beyond the calculator.
The result labels entered employee and employer amounts but does not decide who is taxed currently, whether wages remain subject to FICA, whether a pickup is valid, or when employer money vests. A projected account balance can include unvested amounts only as a scenario. The participant should retain the summary plan description, amendment history, payroll codes, and administrator confirmation beside the calculation.
If an owner distribution later needs a current-year minimum calculation, the 2026 owner RMD calculator addresses a different life-expectancy-table question and should not be used to set contributions.
Stop the 401(a) estimate at the plan-administration boundary
The page does not combine every controlled-group plan, value employer securities, model nondiscrimination testing, calculate corrective distributions, or determine eligibility. It also cannot forecast returns, fees, future limits, or employment continuity. Even a mathematically correct screen can be wrong for the plan when compensation or aggregation facts differ from the inputs.
Use the selected-year result as a question sheet for the employer or recordkeeper. Verify contribution character, compensation definition, related plans, annual additions, vesting, and any 414(h)(2) treatment from authoritative documents. Do not use the estimate to change payroll elections or report taxes without appropriate confirmation. The tool supplies transparent arithmetic, not a fiduciary, tax, benefits, or legal determination.