Sequence-of-Returns Risk Explained: Why the Average Return Is a Lie That Could Bankrupt Your Retirement

Sequence risk is the danger that the timing of investment returns — not their average — determines whether your retirement portfolio survives.

If markets crash early in your retirement while you're withdrawing income, you lock in losses you can never recover from. If the same crash happens later, you've already banked years of gains and your remaining withdrawal period is shorter. Same returns, same withdrawal rate, opposite outcomes.

An example that makes it concrete:

Take £100,000 and withdraw £4,000 at the start of each year (the classic 4% rule). The annual returns over five years are: -20%, -10%, +5%, +15%, +25%. That averages +3% a year.

Now reverse them: +25%, +15%, +5%, -10%, -20%. Same +3% average.

In the first scenario — crash first — the portfolio drops from £100,000 to £76,800 after year one, then to £65,520 after year two. By the end of year five, you have £82,107.

In the second scenario — boom first — the portfolio rises to £120,000 after year one. After five years: £91,746.

That's a £9,639 difference. On the same average return. Across just five years. Stretch this over a 30-year retirement and the gap becomes existential: one portfolio survives, the other doesn't.

The Bank of England base rate currently sits at 3.75%, with long-dated UK gilt yields at 4.82% — meaning bonds actually pay meaningful income again. That changes the defence calculation, which we'll get to.

Sequence risk is a decumulation problem. During accumulation — the 30-40 years you spend building a pension — the order of returns is mathematically irrelevant to the final balance.

Here's why: during accumulation, you're adding money every year. A crash is actually good news — your monthly contribution buys more shares at lower prices. Pound-cost averaging works in your favour. The portfolio eventually recovers and you own more units than if markets had risen steadily.

During decumulation, the arithmetic inverts. You're removing money every year. A crash means you're selling at precisely the wrong moment. You need to sell more units to generate the same £4,000 withdrawal, and those units are never coming back. When the recovery arrives, you have fewer shares to participate in it.

This is not a theoretical concern. A 2023 study by Morningstar analysed US equity returns from 1926 to 2022 and found that a 4% inflation-adjusted withdrawal rate from a 60/40 portfolio survived 30 years in roughly 85% of historical scenarios — but the 15% of failures were almost entirely driven by retiring into the teeth of a bear market. The unlucky cohort that retired in 1966, right before a 16-year stretch of poor real returns, watched their portfolio gutted.

For a UK investor, the context is slightly different. As our CAGR & Total Return explainer explains, the FTSE 100 has returned roughly 7.2% annualised over 40 years — but that average obscures individual years as bad as -31% (2008) and as good as +32% (2009). The sequence in which those years arrive in your retirement is the only thing that matters.

The chart below shows two identical retirement portfolios starting at £250,000, withdrawing £10,000 annually (4%), with the same set of annual returns — just in opposite order:

The red line — bad returns early — runs out in year 24. The blue line — identical average return, different sequence — finishes year 30 with over £226,000.

The cruel thing about sequence risk is that it punishes bad luck, not bad decisions. You could do everything right — save diligently for 35 years, build a sensible 60/40 portfolio, keep costs low — and still see your retirement plan wrecked because you happened to stop working in October 2007 rather than October 2009.

The investment industry's standard response — "stay invested for the long term" — is true but insufficient. Someone withdrawing 4% a year doesn't have a long term when the market drops 40%. They have about 24 months before forced selling does structural damage.

Sequence risk cannot be eliminated, but it can be managed. Here are the five practical defences available to UK investors, ranked from simplest to most sophisticated:

1. The cash buffer (two years of spending)

The cheapest and simplest defence. Hold two years of retirement spending in cash — not invested, not in bonds, actual cash or near-cash in a high-interest savings account or cash ISA. When markets tank, you spend from the buffer instead of selling equities. When markets recover, you refill the buffer from investment gains. This single tactic eliminates the forced-selling-at-the-bottom problem.

2. Variable withdrawal rates

The 4% rule is a planning guideline, not a contract. In a down year, withdraw 3% instead of 4%. Skip the inflation adjustment. The difference between a rigid £40,000 withdrawal and a flexible £30,000 withdrawal during a -20% equity year compounds dramatically over a decade. Research by Wade Pfau found that flexible withdrawal strategies raise the historical survival rate of a 60/40 portfolio from roughly 85% to over 95%.

3. The bond tent

Increase your bond allocation in the five years before and after retirement, then gradually reduce it. The idea: bonds provide ballast precisely when sequence risk is highest — the decade surrounding your retirement date. A bond tent might move from 60/40 to 40/60 at retirement, then glide back to 60/40 over the following decade. With UK gilt yields at 4.82% as of April 2026, the opportunity cost of holding more bonds is considerably lower than it was in the zero-yield era.

4. Bucketing

Partition the portfolio by time horizon. Bucket 1 holds two years of spending in cash. Bucket 2 holds years 3–7 in bonds and income-generating assets. Bucket 3 holds years 8+ in global equities. You spend from Bucket 1, refill it from Bucket 2, and refill Bucket 2 from Bucket 3 when markets are favourable. It's mental accounting — but mental accounting that prevents catastrophic behavioural mistakes.

5. Partial annuitisation

Use roughly 25% of your pension pot to buy a guaranteed income that covers essential spending — food, energy bills, council tax. The remaining 75% stays invested for growth and discretionary spending. This approach — sometimes called a "floor-and-upside" strategy — means market crashes can't take away your ability to eat. Annuities are unpopular in the UK (see our annuity explainer for why), but their function as an insurance product against longevity and sequence risk is irreplaceable.

None of these defences are mutually exclusive. A cash buffer plus variable withdrawals plus a bond tent is entirely practical and costs nothing to implement inside a UK SIPP or ISA wrapper. For more on structuring the portfolio itself, see our rebalancing and asset allocation guide.

For a decade after the financial crisis, bonds yielded essentially nothing. A 10-year gilt paid less than 1% for most of 2019–2021. Selling equities to buy bonds as a defence against sequence risk meant accepting near-zero income — a trade-off that made the bond tent and bucketing strategies much harder to swallow.

That era is over. As of April 2026, long-dated UK gilt yields sit at 4.82%. The Bank of England base rate is 3.75%. Cash ISAs pay 4.5–4.6% at the top end. For the first time since 2008, the defensive assets in a sequence-risk strategy pay you to hold them.

This changes the maths meaningfully. A two-year cash buffer in a 4.5% cash ISA generates roughly £2,250 in annual interest on a £50,000 holding — that's real income, not just capital preservation. A bond tent holding 30% in gilts at 4.82% produces over £3,600 a year on a £250,000 portfolio. These are not trivial numbers.

The risk, of course, is inflation. CPI inflation has been running above 3% in the UK — meaning a 4.82% gilt yield is a real return of perhaps 1.5% after inflation. That's positive, but thin. For more on how inflation interacts with investment returns, see our explainer on Beta and Volatility, which covers real vs nominal risk.

Sequence-of-returns risk is the strongest argument for annuities. An annuity eliminates sequence risk by definition: the insurer absorbs the market volatility and pays you a guaranteed income regardless of what markets do. You trade capital for certainty.

But the price of that certainty varies enormously with interest rates. When base rate was 0.1% in 2021, a £100,000 annuity for a 65-year-old paid roughly £4,500 a year. At 3.75%, the same annuity might pay closer to £6,000. The higher base rate makes annuities better value — but also makes drawdown more defensible, because the cash and bond components of a drawdown strategy actually generate income.

The Pension Drawdown explainer on this site walks through the full drawdown mechanics. The short version: if you need guaranteed income to cover essentials, annuity rates are the best they've been in 15 years. If you can tolerate variable income and want to leave capital to heirs, drawdown with a cash buffer and flexible withdrawals is the better path. Most retirees end up somewhere in the middle — partial annuitisation for essentials, drawdown for the rest.

The one thing you should not do is withdraw a fixed percentage every year without defences and hope the averages work out. As the numbers above demonstrate, the averages might be fine while your specific portfolio goes to zero.