IRS Simplified Method Calculator — Pension Exclusion Ratio

If you made after-tax contributions to your pension plan — common for federal employees (FERS/CSRS), teachers, firefighters, police, and many state/municipal workers — a portion of each monthly payment you receive is tax-free. The IRS requires you to use the Simplified Method (IRC §72(d)(1)) to calculate exactly how much of each check you can exclude from gross income.

This calculator uses the statutory expected-payments table from IRS Publication 939 to compute your monthly exclusion, taxable split, and full recovery schedule.

Why this matters. A federal employee who retired at 65 with $105,000 in after-tax CSRS contributions recovers $500/month tax-free — $6,000/year excluded from gross income. Over the 210-month recovery period that's $105,000 returned to them free of federal tax. Without applying the Simplified Method, they pay tax on money they already paid tax on once.

Item	Amount
Expected monthly payments (IRS table)
Monthly tax-free exclusion
Monthly taxable pension income
Tax-free share of each payment
Months until full investment recovered
Age when exclusion period ends

Your recovery status (as of month 0)
Exclusion already claimed
Remaining investment to recover
Payments remaining until full recovery

How to find your after-tax investment in contract

Your "investment in contract" is the total amount you contributed to the pension plan with after-tax dollars — money on which you've already paid income tax. It does not include employer contributions (those were never taxed and are fully taxable when paid out).

Where to look:

Form 1099-R, Box 5: Your pension payer reports your "Employee contributions / Designated Roth contributions or insurance premiums" annually. For the first year, this number typically reflects lifetime contributions, not just that year's amount. Call your pension administrator to confirm the lifetime total.
OPM retirement letter (federal employees): The Office of Personnel Management sends a retirement package showing your CSRS or FERS contribution total. FERS employees hired after 2013 typically contributed 4.4% of pay; CSRS employees contributed 7–7.5%.
Pension administrator records: For state/municipal pensions (CalPERS, TRS, NYSLRS, PERS, etc.), contact your pension office. Most maintain lifetime contribution records and can provide the total in writing.
Prior W-2 forms: If you know your contribution rate and salary history, you can estimate: sum of (annual salary × contribution rate) for all years of covered service.

Common mistake: Many pension recipients assume their pension income is fully taxable because they never "deposited" money like an IRA. But mandatory employee contributions to a defined-benefit pension plan are made with after-tax dollars — the plan withholds a percentage of each paycheck, just like FICA. That money was taxed when earned and cannot be taxed again when paid out.

Who typically has after-tax contributions

Pension type	Typical employee contribution rate	Notes
CSRS (federal)	7.0–7.5%	Pre-FERS employees; high accumulated basis after 30+ year careers
FERS (federal, pre-2013 hire)	0.8%	Lower rate; modest basis vs. CSRS but still meaningful
FERS (2013–2013 hire)	3.1%	One transition year; rate increased to reduce federal costs
FERS (post-2013 hire)	4.4%	Standard for most current federal employees
State/municipal (teachers, police, fire)	5–12%	Varies widely by plan; CalSTRS is 10.25%, Illinois TRS varies
Military (20-year retirement)	0%	No employee contribution required; military retirement is fully taxable (unless combat-zone exclusion applies)
Corporate defined-benefit (private)	0% (typical)	Most private-sector pensions require no employee contribution; fully taxable. Some older plans differ — check plan documents.

How the Simplified Method works — the rules

The IRS requires use of the Simplified Method when you receive pension or annuity payments from a qualified employee plan (IRC §72(d)(1)). The General Rule (a more complex actuarial calculation) is only used for nonqualified plans and is rarely applicable to standard pensions.

Step 1 — Determine your expected number of monthly payments. The IRS sets this based on your age (or combined ages for a joint annuity) at the annuity start date, using a statutory table:

Single life annuity		Joint/multiple life annuity
Age at annuity start	Expected payments	Combined ages at annuity start	Expected payments
Under 55	360	Under 110	410
55–59	310	110–119	360
60–64	260	120–129	310
65–69	210	130–139	260
70 or older	160	140 or older	210

Source: IRC §72(d)(1)(B); IRS Pub. 939 Tables 1 and 2. These statutory tables have not changed since OBRA '93.

Step 2 — Calculate your monthly exclusion amount.

Monthly exclusion = After-tax investment ÷ Expected monthly payments

Step 3 — Apply the exclusion each month. Subtract the monthly exclusion from your gross pension payment. Report only the remainder as taxable pension income on your Form 1040.

Step 4 — Stop when fully recovered. Continue the exclusion each month until you have excluded your entire investment. After that, 100% of each payment is taxable.

Key rule: the exclusion is fixed. The monthly exclusion dollar amount never changes — not for inflation, COLA increases, or anything else. If your pension COLA increases your benefit by $200/month in year 5, only the original exclusion amount applies; the additional $200 is fully taxable.

Worked example — CSRS federal retiree

Annette retired at age 66 from 32 years of federal service under CSRS. She contributed 7% of salary throughout her career, resulting in a total after-tax investment of $118,400. Her monthly CSRS pension is $4,100 (single life, no survivor election).

Expected payments (age 65–69 table): 210 months
Monthly exclusion: $118,400 ÷ 210 = $563.81/month
Monthly taxable income: $4,100 − $563.81 = $3,536.19
Tax-free share: 13.7% of each payment
Recovery complete: After 210 months (17.5 years, at age ~83.5). After that, the full $4,100 (plus any COLA) is taxable.
Annual tax savings (at 22% marginal rate): $563.81 × 12 × 22% = $1,488/year in reduced federal tax — worth $26,235 over the recovery period.

Report it on your Form 1040, Line 5b. The gross pension amount goes on Line 5a; the taxable portion (after excluding your monthly amount) goes on Line 5b. Your pension payer reports the full gross amount on Form 1099-R — you are responsible for calculating and applying the exclusion. Many retirees skip this step and overpay taxes for years.

What if the pension started before 1987?

Pensions that began before November 19, 1996, and that used the Three-Year Rule (the pre-Simplified Method approach that applied before 1987 legislation) may have a different calculation. Under the Three-Year Rule, if you had already recovered your full investment by the time the rule changed, your payments became fully taxable without applying the Simplified Method. If you're in this situation, consult IRS Publication 939 "General Rule" section or a tax professional — the Simplified Method calculator above does not apply to pre-1987 Three-Year Rule cases.

COLA and benefit increases — how they affect the exclusion

FERS and CSRS retirees receive annual COLA increases that raise the gross monthly benefit. These increases do not change the monthly exclusion amount — that is frozen at the original calculation. So as years pass and COLA compounds, the taxable portion of your pension grows while the exclusion stays fixed.

Example: If Annette's FERS pension grows from $4,100 to $4,600 after five years of COLA, her monthly exclusion remains $563.81. The taxable portion grows from $3,536 to $4,036 — the entire COLA increase is fully taxable.

Rollover vs. keeping the annuity — tax basis implications

If you are still deciding whether to take the lump sum or keep the annuity, after-tax contributions are relevant in a different way:

Keep the annuity: Recover after-tax contributions through the Simplified Method — gradually, over 13–34 years, tax-free each month.
Roll the lump sum to a traditional IRA: Your after-tax contributions become "basis" inside the IRA. You must file Form 8606 every year to track IRA basis and avoid paying tax twice. The basis comes out pro-rata across all IRA distributions (including Roth conversions) — it doesn't all come out first.
Roll to a Roth IRA directly: If the after-tax portion is rolled directly to a Roth IRA and the pre-tax portion to a traditional IRA, you preserve the tax-free character more cleanly. This is called a "split rollover" and requires careful execution — see our Roth IRA conversion guide.

Related calculators and guides

Make sure you're claiming every dollar of your exclusion

Many pension recipients overpay taxes for years by not applying the Simplified Method correctly — especially when COLA, survivor elections, and IRA basis all interact. A fee-only advisor who specializes in pension income can verify your calculation, coordinate it with your Social Security taxation, and model your Roth conversion window. Free match.

Sources

¹ IRS Publication 939 — General Rule for Pensions and Annuities — Simplified Method tables, rules for qualified plans, and expected-payments table (Tables 1 and 2)
² IRS Publication 575 — Pension and Annuity Income — how to apply the Simplified Method on Form 1040, Form 1099-R reporting, and special rules
³ IRC §72(d)(1) — statutory basis for the Simplified Method expected-payments table; tables unchanged since OBRA 1993
⁴ OPM — Federal Employee Retirement Taxes — FERS and CSRS contribution rates and after-tax basis guidance for federal retirees

Expected-payments table values verified against IRC §72(d)(1)(B) and IRS Pub. 939. These statutory table values are unchanged since 1993 and are not subject to annual inflation adjustment. Pension contribution rates verified against OPM guidance (current as of June 2026). This calculator computes federal exclusion only; state treatment of pension income varies — see our State Pension Income Tax guide.