What's covered in this guide?:
Payment Date vs Pay Run Period
Payment Date: The actual day your employee receives their pay (when the money hits their account).
Pay Run Period: The dates when the work was done (e.g., 1st to 30th April).
Note: HMRC bases all PAYE calculations on the payment date, NOT the pay run period.
What the Payment Date Controls
Your selected payment date determines:
Which tax year the pay counts toward (UK tax years run from 6 April to 5 April the next year)
Which PAYE tax month/week it falls into (PAYE months run from the 6th of one month to the 5th of the next)
How much of the employee’s personal allowance is left to use when calculating tax
This overrides any assumptions based on the pay period.
Example: Same Pay Period, Different Payment Dates
Pay Run Period | Payment Date | Tax Year | Tax Month | Notes |
1–31 March | 15 April | New Year (starts 6 Apr) | Month 1 | Treated as first pay of the new tax year |
1–30 April | 15 May | New Year | Month 2 | Second month's tax-free allowance applies |
If you pay April’s wages on or before 5 May, it counts as PAYE Month 1 for tax purposes. But if you pay on 6 May or later, it counts as PAYE Month 2, which changes how cumulative tax is calculated.
Opening Balances vs. Previous Employment Data
When starting payroll mid-year or switching systems:
Use Opening Balances to reflect YTD (year to date) pay your organisation has already made in the current tax year
DO NOT use the "Previous Employment" section unless the employee was paid by a different employer.
This information is filled from the employees P45
Using previous employment incorrectly can make the system think the employee has already earned income elsewhere, leading to higher tax deductions.
For detailed instructions on setting this up in staff profiles, please refer to this guide.
Common Payroll Tax Errors and Solutions
Error | Likely Cause | Solution |
Employee taxed too much | Missing or incorrect opening balances | Update employee’s profile with correct year-to-date pay |
Employee taxed too little | Wrong payment date or no previous pay included | Check pay date and add relevant pay history |
Tax seems to skip a month | Payment date falls into the next tax month | Adjust payment date or understand it reflects a new tax month |
Backdating Payment Dates
You may only backdate a payment date if the employee was actually paid on that earlier date. HMRC uses this date when you submit payroll reports.
Important: Don’t backdate payment dates just to fix tax period errors. Always use the actual payment date.
FAQs
Why is my employee's tax £0 for April?
Why is my employee's tax £0 for April?
It's the first pay of the tax year and their tax-free allowance may fully cover the pay.
Can I backdate the payment date?
Can I backdate the payment date?
Only if the employee was actually paid on that earlier date.
How do I know what tax month I'm in?
How do I know what tax month I'm in?
Count how many payment dates have fallen in the tax year since 6 April. There are various calendars available online.
What if I paid someone in April for March work?
What if I paid someone in April for March work?
It still counts in the new tax year if the payment date is after 5 April.
I paid an employee in April, but the work was done in March. Which tax year does this fall into?
I paid an employee in April, but the work was done in March. Which tax year does this fall into?
It falls into the new tax year if the payment date is after 5 April, regardless of when the work was done.
Final Tips
Always ensure your payment date reflects the true date funds were sent
Use opening balances, not previous employment, when entering prior pay your business made
Double-check the tax month if numbers look unexpected
Need Help?
Contact the Support Team support@workforce.com