My pay run looks wrong — what now?

The basics

Pay runs in draft or calculated state can be re-calculated freely — Calculate is idempotent. So when something looks wrong:

1. Open the run.
2. Click Calculate again after fixing the underlying data.
3. Repeat until the numbers match your expectation.

Only finalised runs are locked.

Common issues

Tax = £0 on an employee

• Missing tax code → add one (Employee > Employment > Tax codes)
• Code is NT (no tax) → confirm intentional
• Earnings below the period personal allowance threshold → expected behaviour

NI = £0 on an employee

• Category C (over State Pension age or director-only-above-PT) → check
• Director with no salary above the PT yet this year → annual cumulative may produce £0 mid-year
• Under-21 (M) or apprentice under 25 (H) — no employee NI saving (only employer)

Negative net pay

• Salary sacrifice exceeding gross — check the sacrifice arrangement
• Student loan deduction > earnings above threshold — bug, contact support

Net doesn't match prior month

• Tax code changed mid-year → cumulative method recalibrates
• Salary sacrifice added → reduces taxable + niable
• Statutory absence opened → SMP/SSP/etc. replace some basic pay
• Bonus or one-off added

YTD looks off

• Mid-year hire missing P45 YTD → enter it as the first tax-code row with notes capturing the totals
• Previous run wasn't finalised → YTD only counts finalised runs

Last resort

If a finalised run was genuinely wrong, you can't un-finalise. Either:

• Adjust in the next run (recommended — mirrors how HMRC RTI corrections work)
• Contact support for a void-and-replace