Income-gap calculator
FIRE calculator with pension income
Estimate how pension income changes a portfolio target while keeping pension start dates, inflation protection, survivor benefits, and the bridge visible.
A pension can shrink the portfolio-funded spending gap, but only after payments begin and only for as long as the chosen benefit continues. Treat a pension as an income stream, not as a reason to ignore timing or survivor risk.
Use the quick calculator for a steady-state estimate, then separately fund any years before the pension starts.
Interactive estimate
Later-income gap calculator
Estimate the portfolio target after Social Security or pension income begins. Fund the years before those payments separately.
Later annual portfolio gap
$42,000
Target after this income begins
$1,050,000
Simple estimate only. It does not include the years before benefits begin, taxes, benefit changes, survivor benefits, fees, or market ups and downs.
Steady-state formula
Portfolio gap = annual spending − pension − Social Security − other durable income. Portfolio target = portfolio gap ÷ planning withdrawal rate.
Pension details that change the answer
- Start date and whether payments are reduced for early commencement.
- Cost-of-living adjustment or loss of purchasing power.
- Single-life versus survivor benefit election.
- Plan credit quality and any benefit limits.
- Taxes and health benefits tied to the pension.
Bridge example
If retirement begins at 55 and a $24,000 pension begins at 60, the portfolio covers five years without that income. Subtracting the pension from every retirement year would understate the amount required.
Frequently asked questions
- How much does a pension reduce a FIRE number?
- Divide reliable annual pension income by the planning withdrawal rate for a steady-state estimate. At 4%, $20,000 corresponds to $500,000, but timing and benefit terms still matter.
- Should a non-COLA pension be treated at face value?
- A level payment loses purchasing power over time. Model it conservatively rather than treating it as constant real income.
- How should a survivor pension be modeled?
- Use the actual survivor election and compare household spending after one death. Do not assume the original payment continues unchanged.
Keep planning
Educational illustration only — not financial, investment, tax, legal, medical, or insurance advice. Calculations use simplified assumptions and do not predict future returns or benefits.