What is a payroll number? In UK payroll, it is a unique identifier an employer assigns to an employee’s payroll record. It helps the payroll system connect pay, deductions, benefits, and reports to the correct employment. It is often shown on a payslip and may also be called a payroll ID.
A payroll number is not the same as a National Insurance number, PAYE reference, employee number, tax code, or U.S. Employer Identification Number. Understanding the distinction helps employees ask the right question and helps employers avoid duplicate or mixed records.
What a payroll number is used for
An employer or payroll provider may use the number to:
- identify one employment record in the payroll system;
- connect pay, tax, National Insurance, pension, and other deductions;
- match payroll data sent to HM Revenue & Customs;
- locate an employee when investigating a payslip or correction;
- separate multiple employments or a re-employment record; and
- link payroll information with HR, time, and finance systems.
HMRC’s reporting guidance refers to the payroll ID as an identifier that must be unique within the employer’s PAYE scheme. A stable ID helps HMRC distinguish the employment and reduce duplicate records.
Where to find a payroll number
Check the payslip first. It may appear near the employee name or be labelled Payroll No., Payroll ID, Employee No., Works No., or a similar term. Labels vary because employers design their own payslips and systems.
If it is not clear, ask payroll or HR. Do not assume that every numeric reference on the payslip is the payroll number; a payslip may also display a PAYE reference, National Insurance number, department, location, or pension reference.
Payroll number compared with other identifiers
| Identifier | Who assigns it | What it identifies | Typical format |
|---|---|---|---|
| Payroll number / payroll ID | Employer or payroll system | One employee’s employment record | Employer-defined letters or numbers |
| PAYE reference | HMRC | Employer PAYE scheme | Usually office number plus employer reference |
| Accounts Office reference | HMRC | Employer payment account | 13 characters |
| National Insurance number | UK government | Individual’s NI and tax record | Letters and numbers, such as QQ123456C-style structure |
| Tax code | HMRC | Instruction used to calculate Income Tax | Numbers and letters, depending on circumstances |
| Employee number | Employer | Internal HR or workforce record | Employer-defined; sometimes same as payroll ID |
| U.S. EIN | U.S. IRS | U.S. business or other entity for federal tax purposes | Nine digits |
An employer may deliberately use the same internal number in HR and payroll, but the terms are not automatically interchangeable. Confirm the system design before changing records or creating integrations.
Does every employee need a payroll number?
Payroll software and HMRC reporting require a way to distinguish employments. The employer decides the format, and an employee generally does not apply to the government for the number. A small employer may use a simple sequence; a larger group may combine location, company, or system codes.
A useful payroll ID should be unique, stable, and not reveal unnecessary personal information. Avoid embedding a birth date, full National Insurance number, or other sensitive data in an internal identifier.
Changing a payroll ID
Changing an ID carelessly can cause HMRC to treat a submission as a new employment and create a duplicate record. HMRC guidance says that when an employer changes a payroll ID, it should report both the old and new identifiers and indicate that the payroll ID has changed.
Before a change:
- Document why the change is needed and which records are affected.
- Check payroll software instructions and HMRC reporting requirements.
- Map the old and new IDs in HR, time, pension, benefits, and accounting systems.
- Test the change before the live Full Payment Submission.
- Review the employee’s Personal Tax Account and employer notices for duplicates or anomalies.
Re-employing a former employee
HMRC’s new-employee guidance says that a person who is re-employed in the same tax year should receive a different payroll ID from the previous employment, and the old and new IDs should be reported appropriately. This helps HMRC identify the records as separate employments.
Do not simply reactivate an old record without checking the payroll software and the facts. Pay, starter information, leaving dates, benefits, pension, and year-to-date values all need correct treatment.
What employees should do if the number is wrong
Contact payroll or HR with the payslip date and the identifier you believe is wrong. Keep copies of payslips, P45, and relevant messages. If tax or National Insurance also appears wrong, check the inputs—not just the payroll number—including tax code, starter declaration, pay period, benefits, and deductions.
Employees should not edit or invent a payroll number themselves. The employer controls the payroll record and must make corrections through the applicable reporting process.
Payroll setup checklist for employers
- Use one unique payroll ID per employment record.
- Define whether payroll ID and employee number are identical or separate.
- Restrict who can create, merge, and change IDs.
- Reconcile new starters, leavers, and rehires before every payroll close.
- Test integrations with time, pension, expenses, and accounting systems.
- Keep an audit trail of changes and corrections.
- Review treatment of taxable benefits using our benefit in kind guide.
The number of annual paychecks is a separate decision. See semi-monthly vs. biweekly pay for a comparison of two common schedules.
Frequently asked questions
Is a payroll number confidential?
It may not be as sensitive as a National Insurance number, but it still belongs to an employment record. Share it only for a legitimate purpose and protect payroll documents containing personal and financial data.
Can two employees have the same payroll number?
They should not share the same payroll ID within the employer’s PAYE scheme. Duplicate identifiers can create reporting and reconciliation problems.
Is a payroll number the same as an EIN?
No. A UK payroll number identifies an employee’s record within an employer’s payroll. A U.S. EIN is a federal tax identifier for an employer or other entity.
Sources reviewed
Last reviewed: August 15, 2026. This article provides general UK payroll information and is not individualized tax, employment, or legal advice.