Tax Code Guide

1257L-M1

Tax Code 1257L M1

What does this code mean?

1257L M1 is the monthly equivalent of 1257L W1. You have the standard £12,570 Personal Allowance, but tax is calculated on a non-cumulative basis each month. This temporary code usually resolves within a few months when HMRC updates your records. In the meantime, you may overpay tax that you can later claim back.

Emergency Tax Warning

This is often an emergency or temporary tax code. You might be paying too much tax while on this code.

Who gets this code?

Monthly-paid workers starting a new job, returning from a career break, or where HMRC needs time to confirm the correct code.

Is it correct?

Check your latest P45 or Payslip to see if this matches your current situation.

Think you overpaid on 1257L-M1?

If your tax code was wrong for even a few months, HMRC might owe you money. Upload your P60 or Payslip to check instantly.

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