Tax Code Guide
W1
Week 1 Emergency Tax
What does this code mean?
W1 is the weekly equivalent of M1. Your tax is calculated on a non-cumulative basis, meaning each week is treated independently rather than looking at your year-to-date earnings. This typically leads to overpaying tax, especially early in the tax year when your cumulative earnings would still be within the personal allowance.
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?
Weekly-paid workers who start a new job, change employers, or are placed on emergency tax. Common in retail, hospitality, and agency work.
Is it correct?
Check your latest P45 or Payslip to see if this matches your current situation.