Payslip Checker for Northampton on Tax Code SD1

Northampton is a mid-sized urban economy of around 250k residents in Northamptonshire. Median full-time gross pay for the area sits near £30,800 per year (ONS ASHE 2024), and most local employees see their PAYE deducted before they ever check the breakdown. This page focuses specifically on what tax code SD1 should look like on a Northampton payslip. Because SD1 is a stable PAYE code, the monthly figures should be broadly consistent across the tax year. England uses the rest-of-UK PAYE bands, so the standard 20% / 40% / 45% rates apply alongside SD1.

What does SD1 mean for Northampton workers?

SD1 applies a flat 42% to every pound under this employment. In Northampton, this is most often a second-job code — for example NHS bank shifts at a local trust on top of a substantive role. For most Northampton employees, SD1 should appear in the same place on every payslip, with the deductions tracking smoothly month to month.

Scottish equivalent of D1. All income under this employment is taxed at the Scottish higher rate (42% in 2026/27). Used on additional sources of income for higher-band Scottish taxpayers.

Effective tax + NI rate on this salary: 46.7%. Estimates based on ONS ASHE median earnings 2024 — your actual pay may differ.

Local context for Northampton

Northampton payslips use the rest-of-UK PAYE bands: 20% basic up to £50,270, 40% higher up to £125,140, then 45% additional above that. National Insurance for a category-A employee is 8% between the primary threshold and the upper earnings limit, then 2% above. Council tax is settled separately via your local authority and is not a payslip line.

Common payroll questions in Northampton

Should my Northampton payslip show tax code SD1?

SD1 should appear if your circumstances match what HMRC expects for this code (scottish higher-rate flat code at 42%.). On a typical Northampton salary of £30,800 you would expect roughly £1,078 of income tax per month under this code.

Why does my Northampton payslip differ from a colleague's on the same code?

Two Northampton colleagues on tax code SD1 can still see different deductions because pension contributions, salary sacrifice, student loan plan, taxable benefits and overtime all sit alongside the tax code. The code only governs the income-tax line. Match the code first, then check pension and NI category, then the variable lines.

How does Northampton compare to other UK cities for SD1 take-home?

Northampton's take-home tracks the rest-of-UK PAYE table directly. The same gross pay anywhere in England would yield the same income tax and NI; differences across cities come from local pay levels, not the tax code itself.

What should I do if SD1 looks wrong on my Northampton payslip?

Start with your most recent payslip and your latest HMRC P2 coding notice. If the code on your payslip does not match the code on the P2, the employer is the right first call. If they match but the figure looks wrong, contact HMRC on 0300 200 3300 — your tax code is set by HMRC, not by your Northampton employer. You can also upload your payslip to PayslipIQ for a free instant breakdown.