# Coast FIRE Calculator With a Pension

> See your Coast FIRE number with a pension and Social Security. Count a pension with no COLA at its real buying power and cover the years before it starts.

Source: https://mycoastfire.com/coast-fire-with-pension-calculator
Last updated: 2026-09-26

Enter your pension, the age it starts and whether it has a cost-of-living adjustment. You'll see how much less you need invested today, with Social Security as an optional second income.

A pension lowers your Coast FIRE number because every dollar it pays is a dollar your portfolio doesn’t have to produce. At a 4% withdrawal rate, $1,000 a year of pension replaces $25,000 of savings. In the example below, a $26,000 pension with no inflation adjustment cuts what a 38-year-old needs invested today by 43%.

How much it cuts depends on two things the calculator asks about: when the pension starts compared with when you stop working, and whether it rises with inflation.

## What does a pension do to a Coast FIRE number?

Renee is 38 and works for a county government. She has $120,000 in her 457(b) and IRA, adds $1,200 a month, and wants to stop working at 60 and spend $52,000 a year. Her plan estimates a pension of $26,000 a year in today’s dollars starting at 60, and her Social Security statement shows $16,000 a year at 67.

| Renee | Social Security only | Pension, no COLA | Pension with a COLA |
| --- | --- | --- | --- |
| Pension counted | $0 | $17,497 | $26,000 |
| Portfolio needed at 60 | $1,012,000 | $574,583 | $362,000 |
| Coast FIRE number at 38 | $437,680 | $248,501 | $156,561 |
| Coast FIRE reached at $1,200 a month | not before 60 | age 49 | age 40 |

Without the pension, her savings rate never gets her to Coast FIRE before 60. With a pension that has no cost-of-living adjustment, she can stop contributing at 49. If the same pension had a COLA, she’d get there at 40. All three columns include the seven years between 60 and 67 when her portfolio pays what Social Security later will.

Load Renee's numbers

Pension $26,000 from 60 with no COLA, Social Security $16,000 from 67. Switch the COLA answer to see the third column.

[Use Renee's numbers](https://mycoastfire.com/coast-fire-with-pension-calculator?age=38&ret=60&spend=52000&assets=120000&contrib=1200&pen=26000&penage=60&ss=16000)

## How the calculator works

It’s the same calculation as our [Social Security calculator](https://mycoastfire.com/coast-fire-calculator-with-social-security), with the pension up front and one extra step for inflation.

```
pension counted   = pension × 1                          with a COLA
                  = pension × average of 1.03^−t, t = 0…29   without one (at 3% inflation)

retirement target = max(spending − pension counted − Social Security counted, 0) ÷ withdrawal rate
                  + pension counted × max(0, pension start age − retirement age)
                  + Social Security counted × max(0, claiming age − retirement age)

Coast FIRE number = retirement target ÷ (1 + real return)^(years to retirement)
```

Enter the pension in today’s dollars, as the amount of the first year’s checks. The “without the pension” figure next to your result keeps everything else the same, Social Security included, so the gap between the two numbers is what the pension is worth to you in savings today. The [methodology page](https://mycoastfire.com/methodology) explains the real return and the month-by-month coast age.

## What if the pension starts after you stop working?

Then your portfolio has to cover the pension’s share of spending until the first check. The calculator adds the counted pension once for every year of the gap, and it assumes that bridge money earns nothing after inflation, which is cautious.

Leaving early usually shrinks the pension too. Say Renee started at 28 and would have 32 years of service at 60. If she stops at 57 instead, she has 29 years, so her benefit drops to about $23,563. If her plan doesn’t raise deferred benefits while she waits, three years of inflation leave it worth about $21,563 in today’s dollars when it starts at 60. Her portfolio now needs $740,762 at 57 instead of $574,583 at 60, and her Coast FIRE number rises from $248,501 to $359,165. At $1,200 a month she never gets there, so she'd be saving right up to the day she leaves. About $74,646 of the higher target comes from the smaller pension alone; the rest pays for three more bridge years before the pension and Social Security start. If you’re aiming for your mid-50s, our [retire at 55](https://mycoastfire.com/retire-at-55) page covers the rest of the gap, from the rule of 55 to health insurance before Medicare.

The other direction is simpler. A police officer or a military retiree might start collecting at 50 and keep working somewhere else until 60. Set the start age before your retirement age and the calculator counts the full pension from day one with no bridge. It doesn’t count the checks you get while still working. If you invest them, add them to your monthly contribution.

## COLA or no COLA: how much does it change?

A lot. Social Security benefits get a [cost-of-living adjustment](https://www.ssa.gov/cola/) each year, and many pensions don’t. A flat pension buys less each year, so its value to you is the average of what it’s worth across your retirement, not the first check.

| Inflation | Share counted over 30 years | $26,000 pension counts as |
| --- | --- | --- |
| 2% | 76.1% | $19,798 |
| 3% | 67.3% | $17,497 |
| 4% | 59.9% | $15,586 |

The 30 years is an assumption, and I think it’s the right one for someone retiring around 60. If you’ll retire at 50, a flat pension has longer to erode and deserves an even smaller share.

Plenty of pensions sit in between. Federal employees under FERS get a [reduced COLA](https://www.opm.gov/frequently-asked-questions/retire-faq/post-retirement/how-is-the-cost-of-living-adjustment-cola-determined/): the full CPI increase when it’s 2% or less, a flat 2% when inflation runs between 2% and 3%, and inflation minus one point above that. Most FERS retirees get no COLA at all until 62. At 3% inflation a FERS pension loses about 1% a year, which works out to about 87% of its value over 30 years. The yes/no switch can’t capture that, so pick yes and enter about 87% of your pension. Teacher pensions vary just as much by state; our [post on Coast FIRE for teachers](https://mycoastfire.com/blog/coast-fire-for-teachers) walks through California and Texas.

## What your pension estimate doesn’t tell you

### Survivor benefits

If you’re married and your plan is a private-sector pension, federal rules make a [joint and survivor annuity](https://www.irs.gov/retirement-plans/plan-participant-employee/retirement-topics-qualified-joint-and-survivor-annuity) the default, paying your spouse 50% to 100% of your benefit after you die. Choosing a single-life payment instead needs your spouse’s written consent, witnessed by a notary or a plan representative. The survivor version pays you less while you’re alive; in PBGC’s [2026 guarantee table](https://www.pbgc.gov/workers-retirees/learn/guaranteed-benefits/monthly-maximum), the cap at 65 is $7,789.77 a month for a single-life annuity and $7,010.79 with a 50% survivor benefit. Enter the amount you’ll actually take. Government plans set their own survivor options.

### Vesting and leaving early

A private pension can make you wait up to five years to own the employer-funded part, or phase it in between years three and seven, according to the [Department of Labor](https://www.dol.gov/agencies/ebsa/about-ebsa/our-activities/resource-center/faqs/retirement-plans-and-erisa). Federal, state and local plans aren’t covered by those rules and write their own. If you leave before you’re vested, you may get back only your own contributions, so the pension you enter here should be zero.

### Lump-sum offers

Some employers offer a one-time payment instead of the monthly check. The [CFPB](https://www.consumerfinance.gov/archive/blog/key-tips-to-consider-if-choosing-a-lump-sum-pension-payout/) points out that the choice can’t be undone and that the money is generally taxed as ordinary income unless you roll it over. If it’s paid to you rather than moved directly into an IRA, the plan has to [withhold 20%](https://www.irs.gov/retirement-plans/plan-participant-employee/rollovers-of-retirement-plan-and-ira-distributions). If you take the lump sum and roll it over, set the pension to zero and add the money to what you have invested. I’d lean toward keeping the monthly check if your plan is well funded and you expect to live a long time, since lifetime income is expensive to buy on your own.

### Who insures the pension

The PBGC insures most [private-sector pensions](https://www.pbgc.gov/workers-retirees/learn/pension-insurance-coverage), but not federal, state, local or military ones. Union multiemployer plans have their own, much smaller [guarantee](https://www.pbgc.gov/workers-retirees/learn/guaranteed-benefits/multiemployer-plans): at most $35.75 a month per year of service, or $12,870 a year after 30 years. If you’re in a union plan with funding problems, I’d count the guaranteed amount, not the promised one.

## Where this calculator falls short

It treats your pension as a fixed number that starts on a set date. It doesn’t know your plan’s early-retirement reductions, so enter the benefit you’d get at the age you plan to claim it. It doesn’t model taxes on the pension or withdrawals, or a partial COLA like the FERS one. It takes one pension, so if your spouse has one too and it starts around the same age, add the two together. Returns are steady until you retire, which real markets never are.

The biggest limit is the one in Renee’s example. A Coast FIRE number built on a pension assumes you stay long enough to earn that pension. If you’re planning to leave, run it twice, once with the pension you’d get by staying and once with the smaller one you’d get by going, and look at the difference.

## Questions people ask

### How do I count a pension in my Coast FIRE number?

Subtract the yearly pension from your retirement spending before you divide by your withdrawal rate. If the pension starts after you stop working, your portfolio also has to pay that amount for each year of the gap. A pension with no cost-of-living adjustment should count for less than its face amount, because inflation shrinks it every year.

### How much of a pension without a COLA should I count?

Its average buying power over your retirement. At 3% inflation over 30 years, that's about 67% of the starting amount. At 2% inflation it's about 76%. The calculator works this out from your inflation input when you answer no to the COLA question.

### Is a government pension insured like a private one?

No. The PBGC insures most private-sector pensions up to a legal limit, but it doesn't cover federal, state, local or military pensions. Those are backed by the government that runs the plan, so how well the plan is funded matters more.

### Can I include Social Security too?

Yes. Open the Social Security section under the pension inputs, enter your estimate from ssa.gov, and pick your claiming age. Leave it at $0 if your job doesn't pay into Social Security and you haven't earned credits elsewhere.

## Keep reading

-   [Coast FIRE for teachersTeacher pensions, 403(b)s and 457(b)s, with state examples.](https://mycoastfire.com/blog/coast-fire-for-teachers)
-   [Coast FIRE with Social SecurityThe same math with Social Security in front.](https://mycoastfire.com/coast-fire-calculator-with-social-security)
-   [Retire at 55What it takes to stop working at 55.](https://mycoastfire.com/retire-at-55)