Keep more of your £12,570 tax-free with smart, legal tactics — whatever your employment situation.
For the 2026/27 tax year, every UK resident gets a Personal Allowance of £12,570. Earn above that and you start paying 20% on the excess — but below it, you keep every single penny. The trick is making sure your allowance is applied in the right place and that nothing erodes it without you knowing.
Many people lose hundreds of pounds a year simply because their allowance is split wrongly between jobs, or because they don't claim the extras they're entitled to. This guide walks through the most effective, fully legitimate ways to protect and maximise your tax-free amount.
If you have a second job on top of your primary role, you must decide which employer receives your Personal Allowance. HMRC does not let you use it in both. The general rule: assign your allowance to the job with the highest earnings. That way, you shelter income that would otherwise be taxed at 40%, rather than just 20%.
Job A: £45,000 per year (higher rate territory)
Job B: £15,000 per year (basic rate only)
Giving your £12,570 allowance to Job A saves you £5,028 in tax (40% of £12,570). Giving it to Job B saves just £2,514 (20% of £12,570). The difference is £2,514 per year — simply by choosing the right job.
To switch where your allowance is applied, contact HMRC and ask them to adjust your tax codes. Job A will get 1257L; Job B will be moved to BR.
If you're married or in a civil partnership, and one partner earns less than £12,570 while the other earns below £50,270, you can transfer £1,260 of unused allowance to the higher earner. That's worth up to £252 in tax relief each year — and it's one of the most commonly missed claims.
Better still, you can backdate the claim for up to four tax years. A couple who missed out on the last four years could receive a lump sum of around £1,000.
Starting a new job without a P45 often triggers an emergency tax code. That means you may be taxed on every pound of your first pay packet, because HMRC hasn't yet received confirmation of your new earnings. The result? You could lose up to £2,514 in a single month.
You can head this off by:
If you do end up on an emergency code, HMRC should correct it automatically within a few weeks once they've processed your details. If not, call them on 0300 200 3300.
If your adjusted net income (total income minus certain deductions and allowances) exceeds £100,000, you start losing your Personal Allowance at a brutal rate: £1 of allowance lost for every £2 earned over £100,000. By the time you reach £125,140, your allowance is gone completely.
The good news: you can keep your allowance by reducing your adjusted net income below the £100,000 threshold. Strategies include:
Use our take-home pay calculator to see how extra pension contributions affect your net income.
Taxable benefits like a company car, private health insurance, or a cheap loan from your employer reduce the tax-free amount shown in your code. HMRC works out the cash equivalent of each benefit and subtracts it from your £12,570 allowance, turning 1257L into something like 1225L or lower.
You can't always avoid this — but you should always challenge it if you think the valuation is wrong. Your P11D form (which your employer sends to HMRC each year) lists every benefit's value. Check it, and if you see something you no longer receive, ask your employer to update their records and tell HMRC.
Several adjustments can either add to or subtract from your Personal Allowance, and many people miss them:
Always log into your HMRC Personal Tax Account and review your estimated income and allowances. If anything looks off, use the "report a change" function to fix it.
HMRC bases your tax code on the income it expects you to earn. If that estimate is too high — say, you left a job mid-year or went part-time — your allowance may be reduced to claw back tax you don't actually owe. The code might show a K prefix or a lower number than expected.
If your income has genuinely dropped (job change, redundancy, maternity/paternity leave, or a shift to freelance work), update your Personal Tax Account immediately. HMRC will recalculate your code, often restoring your full allowance for the rest of the year.
HMRC issues new tax codes in January and February for the following tax year (starting 6 April). Some employers receive the code directly, but many employees still get a PAYE coding notice (form P2) in the post. If you don't receive one, don't assume nothing changed.
If your new code looks wrong — or if your old code carried over without explanation — contact HMRC before the tax year starts. Fixing it early means no emergency tax, no over-deductions, and a smoothly running payroll from day one.
Your £12,570 allowance is yours alone. It doesn't transfer between partners (except via Marriage Allowance, above), and it isn't affected by your partner's income. If you're a stay-at-home parent or a lower earner, your unused allowance is simply lost at the end of the tax year — unless you claim Marriage Allowance.
The system is also not "use it or lose it" in the sense of carry-forward: you can't carry your unused allowance into next year. But if you've overpaid tax in a previous year, you can claim a refund up to four years back. Check our UK tax refund guide to see if you're owed money.
Your Personal Allowance only covers employment and pension income. But you also have separate tax-free buckets that you can use regardless of your salary:
Putting savings in an ISA is the single most powerful way to protect investment returns from tax, and it doesn't affect your Personal Allowance at all.