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CY Clinkanteyoio

Household maths

Spending first. The portfolio number second.

Independence is a spending number divided by a withdrawal rate you are willing to live with. Everything else is an assumption. This page shows the arithmetic and lets you change the assumptions. It does not know your tax, your mortgage, or next year's returns.

Desk still life with a notebook, envelope and pen

Your illustration

Defaults describe a household spending £2,200 a month. Replace every figure with your own.

4% is the figure people quote from US research. 3.5% and 3% are sterner tests. Neither is a safe rate guaranteed for a UK household.

Pensions and ISAs you will not spend before the target age. Do not include the emergency fund or the house you live in.

Real means after inflation, before the spending begins. 4% is optimistic for a cautious plan. Rerun at 3% and at 2%.

Independence number

£754,286

Annual spending divided by the withdrawal rate.

Coast figure today

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What would need to be invested now, with no further contributions, to reach the independence number on the return assumption.

Gap to the coast figure

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Coast figure minus invested assets. Zero means the coast label is met on these assumptions only.

Illustrative monthly amount

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Level monthly contribution, in today's money, that reaches the independence number over the years you chose. Contributions are assumed at month end.

A worked sketch, not a target

Take a household that spends £26,400 a year on the life it actually wants funded. At 4 percent the independence number is £660,000. At 3.5 percent it is £754,286. At 3 percent it is £880,000. The same kitchen produces three different futures because the withdrawal rate moved, not because the family changed.

The full new State Pension in 2026/27 is £241.30 a week, £12,547.60 a year, if you have 35 qualifying years. State Pension age is 66 and is rising to 67 between April 2026 and April 2028. Treat that income, if it still exists in that form when you get there, as a later reduction in what the portfolio must cover. Do not build the whole plan on it. Check your own forecast on the government service rather than borrowing ours.

The personal allowance is £12,570 and is frozen through to April 2031 on the announcements made before this page was written. Withdrawals from a pension are not the same as withdrawals from an ISA. ISA withdrawals are not taxed. Pension income generally is, above the allowances that apply to you. A sum that ignores that difference is a sketch of the pot, not of the spending.

What this page leaves out, on purpose: fund fees, advice fees, tax on assets held outside an ISA or pension, sequence of returns in the first decade of withdrawals, care costs, a move, a divorce, and inflation that does not match the CPI baked into a "real" return. If a decision depends on the last pound in the box above, it is not ready.

The Autumn Budget falls on 28 October 2026, the day after this page was set. Allowances can move. Read ISA and pension for the wrapper rules we are using, and confirm them before you act.