Why Has My Take-Home Pay Changed? Compare the Payslip Lines

Use the previous payslip as a starting point, not proof that the earlier calculation was right. Check the pay date, covered dates and number of hours or days first. A new job, unpaid leave, a changed rota or a different cut-off can change the earnings being paid.

What you can see	What to compare	Useful next step
Gross earnings changed	Hours, overtime, commission, bonus, leave and payroll cut-off	Commission and tax; statutory pay planner
Same gross, different PAYE	Tax code, cumulative basis, taxable pay and year-to-date totals	Check a tax code
NI changed	NI-able pay, pay frequency and NI category	PAYE and NI differences
Pension deduction changed	Contribution basis, method, rate and pensionable earnings	Workplace pension deductions
Loan deduction started or changed	Plan, postgraduate flag, pay-period earnings and payroll notices	Student-loan payslip checks
Another deduction or adjustment appeared	The exact label, amount and employer explanation	Other payslip deductions

Keep gross earnings separate from taxable pay and NI-able pay. Pension arrangements, salary sacrifice and taxable benefits can affect these bases differently. If the gross figure stayed the same, compare each deduction and adjustment rather than assuming your salary fell.

For example, if PAYE is £80 higher and the student-loan deduction is £20 higher, with every other entry unchanged, net pay falls by £100. This is an arithmetic illustration, not an HMRC payroll calculation or a claim that either deduction is wrong. Ask why those two lines changed.

If the figures do not reconcile, first check that you copied all the entries, including reimbursements and other adjustments. Use Compare Two Payslips to organise the differences, and ask payroll about an unfamiliar line.

Compare the complete codes, including any Scottish or Welsh prefix and non-cumulative marker. W1, M1, X or NONCUM indicates emergency/non-cumulative treatment: the current period is considered on its own rather than using the normal cumulative history. A code change or a return to cumulative treatment can alter one payment without a salary change.

Compare the code on the payslip with the code in HMRC’s online service or app. If payroll used a different code, ask the employer to explain it. If the code matches HMRC’s record but your circumstances are wrong, follow the tax-code checking steps. See cumulative versus W1/M1 and emergency tax for the specific treatment.

A one-period checker has no year-to-date history. Its estimate cannot establish that a cumulative adjustment is incorrect or guarantee a refund.

First establish which earnings were actually paid in the period. Do not compare a bonus month directly with ordinary pay and interpret the whole net difference as tax. Ask about the payment period and cut-off if work you expected is missing.

For an occasional payment, National Insurance and loan deductions depend on the relevant pay period; an annual average does not reproduce every payslip. Follow the commission guide or emergency tax on commission guide for those circumstances. For a permanent salary change, use the pay-rise explorer. For changed regular hours, start with the pro-rata calculator.

Leave and statutory pay need their own checks against dates and employer terms. The statutory-pay planner is a starting point; an enhanced employer scheme can produce a different payment.

A pension percentage can apply to a different earnings base from your headline salary. Ask whether a changed deduction reflects the rate, pensionable earnings or the scheme method. Net pay and relief at source provide relief differently; the deduction label alone is not enough. See workplace pensions and relief at source.

For student loans, check the repayment plan and whether a postgraduate loan is also due. Deductions use pay-period thresholds, so an occasional higher payment can trigger a deduction even when ordinary pay did not. Ask payroll what notice and plan it used, then follow the student-loan checking guide. Do not assume a refund will be automatic.

Give payroll the pay date, period, changed line and the two observed amounts. Include the relevant contract, hours or commission record where it helps. Ask which earnings base, tax code/basis or deduction instruction was used, rather than declaring the entire payslip wrong.

The payslip checker can create an editable payroll query pack from a result, including the assumptions and limitations. Review it before using your employer’s private payroll channel. The payroll checklist explains what evidence to gather. Keep full payslips and personal identifiers out of public comments.

This is general guidance, not a professional review of your circumstances.