How Long Will My Retirement Savings Last?

The safe withdrawal rate tells you a rate that historically didn't fail. This calculator answers the more direct question: given your actual portfolio and spending, how many years does your money last — and at what age does it run out? Enter your numbers and get a year-by-year drawdown table.

Retirement portfolio longevity calculator

Defaults show a typical early retiree: age 52, $2M portfolio, $70K/year spending, Social Security starting at year 15 (age 67). Adjust to your situation and click Calculate longevity.

Why early retirees need this calculator

The safe withdrawal rate (SWR) — 4% for 30-year retirements, 3.5% for 40-year, 3.0% for 50-year — answers a specific question: what spending rate has historically survived every retirement window in the dataset? That's useful as a ceiling. But it doesn't tell you how close to the edge your specific plan sits.

This calculator answers a different question: given your portfolio and your spending, how many years does the money actually last? If you retire at 52 with $2M and spend $70,000/year, the SWR check tells you "you're near the 3.5% threshold." This calculator tells you your portfolio lasts 48 years to age 100 — or 31 years to age 83, depending on your return assumption. Knowing the actual number changes how you plan.

What "real return" means and why it matters

The calculator uses real (inflation-adjusted) returns and flat real spending. This means:

• Your $70,000/year spending figure is in today's dollars and stays constant in purchasing power — inflation adjustments are implicit
• The expected return you enter should also be real (net of inflation). A 60/40 portfolio with a 7% nominal return and 2% inflation has a ~5% real return
• Common real return assumptions: conservative = 3–4%, moderate = 4–5%, aggressive = 5–6%

The simplification this calculator makes: it assumes a constant return each year. Real markets are volatile — years alternate between strong and weak. A 5% real return achieved as 40 straight years of 5% looks very different from 5% achieved as alternating +20% and -10% years, because the sequence matters when you're withdrawing. See the note on sequence risk below.

How Social Security and pension income extend longevity

Other income sources — Social Security, a pension, or part-time work — reduce the amount you need to draw from your portfolio. The effect compounds over time:

• $25,000/year from Social Security starting in year 15 reduces annual portfolio withdrawals by $25,000 for every year after that
• The portfolio that would otherwise be depleted at age 78 might now last to age 94, because the draws are smaller for the last 20+ years
• This is why delaying Social Security — even by 5–8 years — can dramatically extend portfolio longevity for early retirees

The calculator's "other income" field captures this. Enter your estimated Social Security benefit in today's dollars and the year you plan to start claiming. If you retire at 52 and plan to claim at 67, that's year 15.

Note: Social Security benefits are calculated based on your 35 highest-earning years. Early retirees typically have zero-earning years that reduce the benefit. The Social Security timing guide includes a break-even calculator and a zero-years penalty table specific to early retirees.

The sequence-of-returns problem this calculator doesn't capture

This calculator assumes a steady constant return each year. Real markets don't work that way — and for early retirees, the order of returns in the first 10 years of retirement matters enormously. A 40% market drop in year 2 of retirement is far more damaging than the same drop in year 25, because early losses force you to sell more shares to cover spending.

The gap between a "lucky" and "unlucky" sequence — same average return over 40 years, different year-by-year order — can be $1M+ in portfolio value at retirement's end. For a true probability-weighted analysis that runs hundreds of random return sequences, use the Monte Carlo retirement simulator, which shows your plan's success rate across 1,000 scenarios.

The sequence-of-returns risk guide explains how bond tents, bucket strategies, and the Guyton-Klinger guardrails reduce this exposure for early retirees.

What changes if you spend more vs. less

The sensitivity table in the calculator results shows longevity at 80%, 90%, 100%, 110%, and 120% of your entered spending. The non-linearity surprises most people: going from $70K/year to $77K/year (10% more) may cut 8 years off the portfolio — not 10%. That's because the portfolio compounds longer at lower spending, which means those later years are doing more work. Conversely, trimming 10% can add more years than expected.

This non-linearity is why flexible spending rules — like the Guyton-Klinger guardrails — can add years to a plan without cutting expected spending significantly. A small reduction in a bad year preserves enough compounding to more than make up for it.

Key thresholds to watch

As you adjust the calculator, two thresholds are worth monitoring:

ACA subsidy cliff (~$63,840 single / ~$86,640 MFJ, 2026): If your portfolio draws plus any other income stay below the 400% federal poverty level threshold, you may qualify for thousands of dollars per year in ACA premium tax credits before Medicare at 65. See the healthcare before 65 guide for details on coordinating withdrawals with ACA eligibility.³

IRMAA tier-1 ($109,000 single / $218,000 MFJ, 2026): Medicare premiums are set by your MAGI from two years prior. Large Roth conversions or portfolio draws at ages 63–64 that cross IRMAA tier-1 will raise your Medicare premiums when you turn 65. See the withdrawal order guide for sequencing around IRMAA.⁴