Sequence of Returns Risk: Why the First Years of Retirement Matter Most

Two people can retire with the exact same portfolio size, the exact same withdrawal rate, and the exact same average annual return over 30 years — and still end up with completely different outcomes, one running out of money and one finishing with more than they started. The difference is sequence of returns risk, and it's one of the least intuitive but most important concepts in retirement planning.

What sequence of returns risk actually means

Sequence of returns risk is the danger that the order in which you experience investment returns matters just as much as the average return itself, specifically because you're withdrawing money at the same time. A portfolio that earns -15%, +20%, +10% over three years ends up in a very different place than one earning +10%, +20%, -15% in that order, even though the average return is identical — because in the first sequence, you're forced to withdraw a fixed dollar amount from an already-shrunken balance, permanently locking in a larger percentage loss.

Why this only matters once you start withdrawing

During the accumulation phase, before retirement, sequence of returns risk barely matters — a market crash early in your career just means you're buying shares at lower prices with your ongoing contributions, and a recovery later benefits your entire portfolio. The moment you start withdrawing a fixed amount for living expenses, though, every downturn forces you to sell a larger share of a shrinking portfolio to generate the same income, which is exactly the mechanism that makes early losses so much more damaging than later ones.

A simplified example

Imagine retiring with 1,000,000 dollars, withdrawing 40,000 dollars a year (adjusted for inflation), with a market that drops 30% in year one before recovering to its long-run average afterward. That first-year crash, combined with your withdrawal, might leave you with roughly 660,000 dollars heading into year two — a much smaller base for the recovery to compound on than if the crash had happened in year fifteen instead of year one, even though the total market return over the full period ends up the same either way.

Why this matters more for people retiring early

Someone retiring at 65 with a 25-30 year horizon faces sequence risk mainly in the first five to ten years of retirement, since that's roughly when a bad sequence does the most damage relative to total plan length. Someone retiring at 35 or 40 with a 50-60 year horizon has a similarly dangerous early window, but a much longer subsequent period during which the portfolio still needs to perform — meaning the early years matter just as much in absolute terms, while the total time horizon over which recovery must happen is significantly longer.

Strategies that reduce sequence risk

A cash buffer covering one to three years of expenses, held outside the market, lets you avoid selling depressed investments during a downturn by drawing from cash instead, giving the portfolio time to recover before you're forced to sell into weakness. A flexible withdrawal strategy, where you spend somewhat less during a down market and more during a strong one, achieves a similar effect by reducing how much you sell when prices are low. Starting retirement with a somewhat lower withdrawal rate than the standard 4% also builds in a margin specifically to absorb a bad early sequence without running the plan into serious trouble.

Common mistakes related to sequence risk

A common mistake is treating a single average return assumption in a spreadsheet as if it captures the real risk in a retirement plan, when the actual risk is concentrated in specific bad stretches, not the long-run average. Another mistake is panic-selling during an early downturn, converting a temporary, recoverable dip into a permanent, locked-in loss at exactly the worst possible time. A third is failing to build any buffer or flexibility into the plan at all, leaving no tools available if the first few years of retirement happen to coincide with a market downturn.

Modeling this with your own numbers

The FIRE Calculator above uses an average expected return to project your timeline, which is a reasonable simplification for the accumulation phase, but once you're within a few years of your target date, it's worth stress-testing your plan against a hypothetical early downturn rather than relying solely on the average-return projection — specifically by asking whether your plan could absorb a 20-30% drop in the first year or two of retirement without forcing a change in your spending or your target date.

Why this argues for flexibility over rigid rules

None of this means the 4% rule or a fixed withdrawal schedule is useless — it means the most robust retirement plans build in some capacity to adjust spending in response to how the market actually behaves in the first several years, rather than committing to a completely fixed plan regardless of what happens. A plan that can flex by even a modest amount during a bad early sequence is meaningfully more resilient than one that can't, even if both start from the exact same portfolio and withdrawal rate.