The 4% rule explained

What you'll learn

Understand the 4% rule as a rule of thumb, and the caveats that come with it.

The 4% rule is a rule of thumb for how much you can take from an investment pot in retirement. The idea: withdraw 4% of the pot in your first year, then increase that pound amount with inflation each year, and the pot has a good chance of lasting roughly 30 years.

Flip it around and it gives you a target: to draw a given income, you need a pot of about 25 times that amount.

Where it comes from

The rule grew out of historical studies of past US market returns. That is its strength and its weakness - it is grounded in real data, but past performance does not guarantee the future.

The big caveats

Treat 4% as a starting point, not a settled answer.

CaveatWhy it matters
Not a guaranteeIt is based on history; future returns are unknown
Sequence riskPoor returns early on can permanently shrink the pot
Ignores tax and feesYour real spendable income may be lower
Fixed 30-year horizonEarly retirees may need the pot to last much longer

Sequence-of-returns risk is the one that catches people out: withdrawing money while markets are down early in retirement can do lasting damage, even if average returns later look healthy.

How people use it

As a back-of-envelope guide, the 4% rule is useful for setting a rough target. Many planners use a more cautious rate or keep a cash buffer to ride out bad years. This is education, not a recommendation for your circumstances.

Key takeaways

  • The 4% rule suggests drawing 4% of your pot in year one, then rising with inflation.
  • It implies a target pot of around 25 times your desired annual income.
  • It is a rule of thumb from historical data, not a guarantee.
  • Sequence-of-returns risk, tax and a longer horizon are real reasons to stay cautious.
Illustrative: pot needed to support a given yearly income at 4%
£16,000 a year£400,000
£24,000 a year£600,000
£40,000 a year£1,000,000

Illustrative only, applying the 4% rule of thumb (annual income divided by 4%, the same as multiplying by 25). It ignores tax and assumes the rule holds, which is not guaranteed. This is not a forecast.

Frequently asked questions

Is the 4% rule guaranteed to work?

No. It is a rule of thumb drawn from historical analysis of past market returns. The future may differ, so treat it as a planning guide, not a promise that your money will last.

What is sequence-of-returns risk?

It is the danger of poor returns early in retirement. Selling investments to live on while markets are down can shrink the pot so much that it struggles to recover, even if average returns later look fine.

How might someone make their plan more robust?

Common approaches include using a more cautious withdrawal rate, keeping a cash buffer, and being willing to trim spending in bad years. These are concepts to consider, not advice for your situation.

General information, not financial advice. The value of investments can fall as well as rise, and figures and rules can change; check the current position before acting.