A lump sum arrives — inheritance, redundancy, a house sale. The unhurried sequence: debt, buffer, wrappers, the tax on what the money earns next, and the £2,880 trick for a non-earning partner.
Windfalls are usually grief plus a deadline that doesn't exist. The first rule is that there is no first rule: inherited money in a savings account loses only a little to inflation while you think, and every costly windfall mistake — the rushed investment, the product someone sold, the loan to a relative — comes from acting fast. Park it, breathe, then work the sequence.
It's the same ordering that answers most money questions, applied at once instead of monthly. Clear expensive debt first — settling a 22.9% card is a 22.9% guaranteed return, and no investment offers that. Fill the emergency buffer to 3–6 months of spending. Then shelter the rest as fast as the wrappers allow: £20,000 per person per tax year into ISAs (£40,000 for a couple, and again on 6 April), and pension contributions up to your annual allowance — with carry-forward letting a large windfall use up to four years of allowances at once, relief included, if your earnings support it.
Inheritance tax was the estate's bill, not yours — inherited cash arrives tax-free. What's taxed is what the money earns next: interest above your savings allowance, dividends above £500, gains above £3,000 — which is exactly why the wrapper sequence matters. Two often-missed moves: a non-earning partner can still contribute £2,880 to a pension each year and receive £720 of relief (£3,600 gross, for nothing); and inherited assets arrive at probate value, so gains before you sell are usually small — selling and re-sheltering early beats holding an accidental GIA portfolio for sentiment.
Then the real question: what does this money change? A windfall is a plan input, not a plan. Drop it into your Hundred Summers projection as the lump-sum event it is and see the honest answer — an earlier retirement date, a cleared mortgage, funded school fees — rather than a number sitting in an account waiting to be dribbled away.