PayBreakdown - Salary Calculator & Budget Manager
Why has my tax code changed?
A tax code can change because of a new job, company benefits, previous tax owed, second income, pension income, or updated HMRC information.
What this page helps with
HMRC may change a tax code when it receives new information about your income, benefits, previous underpaid tax, employment changes, or pension income. The changed code can alter monthly take-home pay.
Official sources
Income Tax rates and Personal AllowancesNational Insurance rates and categoriesStudent loan repayment thresholdsPension tax reliefNational Minimum Wage and National Living Wage ratesStatutory Maternity Pay and LeaveStatutory Sick PayFCA guidance on misleading financial promotionsOff-payroll working and IR35 guidanceUnderstanding off-payroll workingSalary sacrifice for employersNHS Employers pay scales 2026/27NHS Health Careers Agenda for Change pay ratesLast updated 2026-05-07. Planning estimates only. Not financial advice.