The SRS earnings test reads simply in the statute: $1 for every $2 above the exempt amount. The reality on the page is a little more forgiving and a little more irritating at the same time. Withholding is annualized, reported on a pay-period basis, and reconciled at year end. If you understand the cadence, you can avoid the most common over- and under-withholding traps.

Here is how the mechanics actually work — in the order OPM applies them.

Step one: OPM asks for your estimate.

When your FERS retirement is processed, OPM gives you a chance to declare an estimated amount of post-retirement earned income for the year. The estimate drives initial SRS withholding. Many retirees report zero, even when they plan to work, because they assume the SRS is theirs by right. It isn’t.

Reporting zero when you actually plan to work creates the most common problem I see: a year-end bill, a refund request, and a smaller SRS the following year. Be honest about your earnings on the form.

Step two: OPM calculates the withholding per pay period.

The SRS is paid monthly, but the earnings test is calculated on a year-by-year basis. OPM divides your estimated excess earnings for the year by 12 (or by the number of months remaining in the year if the SRS starts mid-year) and withholds that much SRS each month.

Example: monthly SRS is $1,200. Estimated excess earnings for 2026 are $10,000. Withholding is $5,000 over the year (the 50% rate), or about $416 per month. The retiree receives $784 of SRS that month instead of $1,200.

Step three: OPM reconciles at year end.

Early in the following year, OPM asks for your actual earnings for the previous year. You provide either a wage statement or a self-employment earnings report. OPM compares actual earnings against the estimate and adjusts the SRS going forward.

Two outcomes are common:

  • Over-withholding. If your actual earnings were lower than estimated, OPM refunds the excess SRS withheld. The refund usually arrives as a lump sum.
  • Under-withholding. If your actual earnings were higher than estimated, OPM increases withholding for the remaining months of the SRS to recover the difference. If the SRS would have ended anyway, there is no balance to recover from.

The non-pay-period math that confuses people.

The earnings test is calculated on calendar-year earnings, not on a single paycheck. If you earn nothing in January through April and then start a high-paying job in May, the test still applies to your full-year total, prorated across the months you received SRS. This can mean a sudden, painful adjustment in December when OPM catches up.

Conversely, if you earn heavily in January through June and then stop working, the test is still applied to the months you actually received SRS, and any over-withholding is refunded. The earnings test does not “reset” when your job ends.

The “grace month” at the end.

The SRS ends the month the retiree turns 62. For a retiree who turns 62 in, say, October, the SRS earnings test applies to months January through October only. Earnings in November and December are not counted against the SRS — not because of any special rule, but because the SRS itself is no longer being paid to be reduced.

This is one of the few windfalls in the SRS structure: if you have to choose a year to exceed the earnings test by a lot, the year you turn 62 lets you keep your earnings high in the last few months without SRS consequences.

Where the surprises hide.

Most SRS withholding disputes come from one of three places: misreported estimates at retirement, midyear earnings changes that nobody reported, and self-employment income that showed up on a 1099 instead of a W-2. All three are avoidable by reading the reconciliation letter OPM sends each year and responding promptly.

The earnings test isn’t a trap. It’s a math problem applied to your actual life. Treat it that way, and the answer is predictable.