Start with the jigsaw, not the pieces

Most conversations about retirement income focus on how much you can safely take. The more valuable question is often which pot you take it from. A pension, an ISA, a general investment account and plain savings are all taxed in different ways, and the order you draw on them can move your tax bill by thousands of pounds across a retirement.

The good news is that you do not need to be a tax expert to get this broadly right. You need to know a handful of numbers, understand how they interact, and review the plan once a year. Here is how to think about it.

Use your personal allowance deliberately

Everyone gets a personal allowance — currently £12,570 — and it is wasted if you do not use it. Pension income, the State Pension and most other income all count towards it.

The State Pension is the complication. If you receive the full new State Pension, that alone uses up most of your allowance before you have touched a private pension. So check your State Pension forecast first, because it determines how much allowance is genuinely spare.

Where there is spare allowance, it usually makes sense to fill it with taxable pension income rather than taking everything from your ISA. You pay 0% on that slice, and you preserve your tax-free ISA money for later years when it can do more work. Watch the basic rate band too: once your income passes it, further pension withdrawals are taxed at 40%.

Do not forget the 25% tax-free lump sum on defined contribution pensions. Drawing it in stages can be smarter than taking it all at once, because the remainder stays invested and you are not pushing a large sum into a taxable year.

Keep an eye on the £100,000 cliff edge

Between £100,000 and £125,140 of adjusted net income, your personal allowance is withdrawn at £1 for every £2 earned. The effect is an effective marginal rate of 60% on that band of income.

This matters even in retirement, particularly if you are taking a large one-off withdrawal for a big purchase, or if you have rental or dividend income alongside your pensions. If a withdrawal would tip you into that zone, consider taking part of it from an ISA or from savings instead. Spreading a large withdrawal over two tax years is frequently the simplest fix of all.

A workable order of withdrawals

There is no single correct order, but this sequence works well for many people:

• Take enough taxable income to use your personal allowance and, where helpful, the rest of the basic rate band.
• Top up from ISAs, which are completely free of UK income tax and capital gains tax.
• Use savings interest, remembering the personal savings allowance — £1,000 for basic rate taxpayers, £500 for higher rate, and nothing for additional rate. If your other income is low enough, the £5,000 savings starting rate may also apply.
• Sell from a general investment account, using your £3,000 capital gains tax annual exempt amount and considering bed-and-ISA style switching to shelter future growth.

Keep cash for two to three years of spending so you are never forced to sell investments at a bad moment or take a withdrawal that pushes you into a higher band.

Thresholds that affect more than your tax bill

Tax rates are only part of the picture. Several thresholds trigger other costs:

• Marriage allowance lets a non-taxpaying spouse transfer part of their allowance, worth up to about £250 a year.
• The High Income Child Benefit Charge begins at £60,000 of adjusted net income and claws back the whole benefit by £80,000.
• Tax-free childcare and free childcare hours are generally unavailable once adjusted net income passes £100,000.

If any of these apply, keeping income just below the line can be worth more than the income itself.

A short yearly routine

Once a year, add up your expected taxable income from all sources: State Pension, private pensions, work, rent, interest and dividends. Compare it to your allowance, the basic rate limit and the £100,000 mark, then decide which pot tops up the rest.

One warning if you are still contributing to a pension: flexible drawdown triggers the money purchase annual allowance, cutting your annual allowance to £10,000. Taking only your tax-free lump sum does not normally trigger it, so check before you act if contributions matter to you.

Finally, remember that Scottish taxpayers have different bands, and that thresholds and allowances change. A little planning each spring is usually enough — and if your affairs are complicated, an hour with a regulated adviser is money well spent.