How does the Marriage Allowance affect my tax code?

Full answer

The Marriage Allowance changes both partners' tax codes to reflect the transfer, and understanding what your new code means helps confirm the claim has been applied correctly. **The recipient's code: M suffix** If you receive the transferred allowance, your standard Personal Allowance of £12,570 increases by £1,260 to £13,830 for 2026/27, reflected in a tax code like 1383M -- the M suffix specifically confirms you have received a Marriage Allowance transfer from your partner. **The transferring partner's code: N suffix** The partner who gives up part of their allowance sees their code change to reflect a reduced allowance of £11,310 (£12,570 minus £1,260), shown as 1131N -- the N suffix confirms this is a Marriage Allowance transfer OUT rather than a standard reduced allowance for some other reason. **Why the transferring partner usually loses nothing** Since the Marriage Allowance can only be claimed where the transferring partner earns below the full £12,570 Personal Allowance in the first place, they were not going to use their full allowance anyway -- so reducing their code to 1131N does not typically create any actual tax liability for them, as their income remains below even the reduced allowance. **How long the codes remain in place** Once claimed, the Marriage Allowance transfer continues automatically each subsequent tax year (with the codes adjusting for the frozen or changing Personal Allowance figures) until either partner cancels the arrangement or a change in circumstances (divorce, one partner's income rising above the relevant thresholds, or death) ends eligibility. **What if your code shows something unexpected** If you have claimed Marriage Allowance but your code does not show the M or N suffix, or shows a different unexpected code, check your Personal Tax Account to confirm the claim was processed correctly -- occasionally claims can be delayed in processing, particularly if made close to a tax year boundary. **Interaction with other code adjustments** The M or N suffix can combine with other tax code adjustments (such as if you also have untaxed benefits in kind or other income affecting your allowance), in which case your code number may differ from the simple 1383 or 1131 figures shown here, while the M or N letter still confirms the Marriage Allowance element is included. **Practical tip** After making a new Marriage Allowance claim, check both partners' next payslips or pension statements to confirm the updated codes have been applied by your employer or pension provider -- there can occasionally be a short delay between HMRC processing the claim and your payroll department receiving and applying the updated code.

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More answers

• What is the Marriage Allowance and who can claim it?
• What does my tax code mean and how do I check if it is right?