TSP Rule of 55: Avoid a Costly 10% Early Withdrawal Penalty

The short answer: The TSP rule of 55 lets federal employees who leave service during or after the calendar year they turn 55 take TSP withdrawals without the IRS 10% early withdrawal penalty. Separation timing controls eligibility here, not the age at which the money actually comes out.

What are the key takeaways?

• IRS Publication 575 exempts qualified plan payments taken “after your separation from service in or after the year you reached age 55” from the 10% additional tax.
• TSP lists the same exception for “payments made after you separate from service during or after the year you reach age 55.”
• Public safety employees defined in IRC section 72(t)(10)(B)(ii) reach the threshold at age 50, or at 25 years of service under the TSP, whichever comes first (IRS Publication 575).
• The IRS marks this exception “yes” for qualified plans and “no” for IRAs, and Form 5329 exception code 01 says it “doesn’t apply to IRAs.”
• 2026 TSP limits are $24,500 elective deferral, $8,000 catch-up, and $11,250 for ages 60 to 63 (TSP Bulletin 25-3).

What is the TSP rule of 55?

The TSP rule of 55 is a nickname, not a statute. It describes one exception to the 10% additional tax the IRS applies to early retirement plan distributions. IRS Publication 575 lists the exception as covering money paid from a qualified retirement plan “after your separation from service in or after the year you reached age 55.”

The Thrift Savings Plan describes the same exception in its own booklet. TSP lists “payments made after you separate from service during or after the year you reach age 55” among the withdrawals that escape what it calls the early withdrawal penalty tax.

Two numbers matter. The penalty is 10% of the taxable portion. The general threshold age is 59½. The exception exists because Congress recognized that some workers leave career jobs well before 59½.

Why does the year you separate matter more than your birthday?

This is the detail that trips people up. The test is a calendar-year test, and it applies to your separation date.

You qualify if you separate at any point during the calendar year you turn 55. A May birthday does not force you to wait until May. Leaving in February of that same year still counts.

The reverse also holds, and it is less forgiving. Separating before that year closes the door permanently. IRS Publication 575 works through an example of a taxpayer who took a distribution in the year he turned 55. Because he had separated from service earlier, he “didn’t meet the requirements for the exception.” Waiting until 55 to withdraw does not repair an early separation.

So a federal employee who resigns at 52 does not gain the exception by leaving the money alone for three years. That person faces the 10% additional tax on TSP withdrawals until 59½.

Who qualifies at age 50 instead of 55?

Certain federal groups reach the threshold five years earlier. IRS Publication 575 names them: federal law enforcement officers, federal customs and border protection officers, federal firefighters, air traffic controllers, nuclear materials couriers, members of the United States Capitol Police, members of the Supreme Court Police, and diplomatic security special agents at the State Department.

For this group the rule reads differently. Publication 575 describes eligibility “after separation from service on or after they reach age 50 or with 25 years of service under the plan, whichever is earlier.” TSP frames the second half as 25 years of service under the TSP.

The 25-year alternative can matter more than the age. An officer who entered federal service at 23 could reach 25 years of TSP service at 48.

Does rolling your TSP into an IRA cancel the exception?

Yes, for the money that moves. The IRS marks the separation-from-service exception “yes” for qualified plans and “no” for IRA, SEP and SIMPLE accounts, so a rollover before 59½ can put the 10% additional tax back on later withdrawals.

The full mechanics — the exact Form 5329 language, a dollar-for-dollar comparison, and how a partial rollover behaves — are covered in Does rolling your TSP into an IRA cancel the age-55 penalty exception?

How does the 10% penalty differ from tax withholding?

These are two separate obligations, and confusing them produces surprises at filing time.

Withholding is a prepayment of ordinary income tax. IRS Publication 575 notes that for an eligible rollover distribution, “20% of it will generally be withheld for income tax.” TSP applies that 20% figure to eligible rollover distributions.

The 10% additional tax sits on top. IRS Topic No. 558 flags the gap directly: “if your distribution is subject to the 10% additional tax, your withholding may not be enough.” The IRS notes that estimated tax payments may be required.

One more caveat on the 20% figure. It is mandatory on eligible rollover distributions, not on every TSP withdrawal. Installments expected to last 10 years or more, and required minimum distributions, follow different withholding rules. Our post on TSP required minimum distributions covers the RMD side.

What happens at age 59½?

At 59½ the rule of 55 stops mattering. The general threshold has arrived, and no separation is required at all.

TSP allows age-59½ in-service withdrawals for participants still working. TSP states that it determines age “based on the date of birth reported by your employing agency or service.” The minimum is $1,000 or the entire vested balance. Participants may take up to four of these withdrawals per calendar year.

Notice the contrast. The age-59½ withdrawal turns on an actual birthday. The rule of 55 turns on a calendar year. Two adjacent rules, two different clocks.

What do the 2026 contribution limits look like?

Anyone weighing an early separation tends to look at what is still going in. TSP published its 2026 limits, and TSP Bulletin 25-3 lists the same figures.

The elective deferral limit is $24,500. The catch-up limit for ages 50 to 59, and for age 64 and over, is $8,000. Participants who are 60, 61, 62 or 63 have a higher catch-up limit of $11,250. The annual additions limit is $72,000.

One 2026 change affects higher earners. TSP states that catch-up contributions must be Roth starting January 1, 2026 for participants whose prior-year FICA wages exceeded $150,000.

What else do federal employees ask about the TSP rule of 55?

Does the TSP rule of 55 apply to a FERS pension?
No. The 10% additional tax applies to retirement plan distributions. A FERS annuity is not a plan distribution, so this exception is not relevant to it. Age and service rules for the annuity itself work separately, as our guide to FERS deferred retirement rules describes.

I separated at 54 and turn 55 next month. Do I qualify?
Based on the Publication 575 example, separation in an earlier calendar year does not satisfy the test. The IRS looks at the year of separation.

Do I need to file anything to claim the exception?
The IRS states that Form 5329 is used when box 7 of Form 1099-R does not show the exception, or shows an incorrect code. The additional tax itself is reported on Schedule 2 of Form 1040.

Are life-expectancy installments treated differently?
TSP lists “substantially equal payments over your life expectancy” as a separate exception. TSP also warns that the penalty tax “can be applied retroactively” if those installments stop, switch to fixed dollar amounts, or are supplemented by another distribution within five years of starting or before 59½, whichever comes later.

Is the 10% penalty charged on the whole withdrawal?
TSP describes the penalty as applying to “any taxable portion of the distribution or withdrawal not rolled over.” Amounts rolled over directly are not part of that calculation.

Where does TSP document all of this?
The TSP booklet Withdrawing from Your TSP Account collects the exception list. IRS Publication 575 and IRS Topic No. 558 cover the tax side in more detail.

Want to walk through your own numbers?

The rule of 55 rarely stands alone. It interacts with annuity timing, health coverage, and the order in which accounts get tapped. Fed Pilot runs free federal retirement workshops that cover how these pieces fit together for federal employees approaching retirement.

Register for a free Fed Pilot workshop and bring your questions.