What it means
Payroll withholding depends on accurate employment and tax information, so a new employer needs details of the previous employment to calculate the appropriate deductions. The P45 supplies part of that handover: GOV.UK says it includes total pay and tax from 6 April until the leaving date, together with the tax code and personal details such as the National Insurance number.
These are employment and tax records, not merely a statement of the employee's final take-home payment. When starting a new job, the employee gives the P45 to the new employer.
For a paper P45, GOV.UK says to give Parts 2 and 3 and keep Part 1a. The employee should retain their own record rather than surrender every part without checking the instructions.
An employee who is not working and claims taxable benefits may need to give the P45 to Jobcentre Plus. Its use therefore is not confined to a direct job-to-job move.
The relevant process depends on the individual's circumstances. If a previous employer did not provide one, the employee should ask that employer.
If it was lost or the employer says it was sent but not received, GOV.UK says a replacement cannot be obtained. A starter checklist can be used instead for the new employment process.
A person starting their first job or an additional job also uses a starter checklist. Lack of a P45 does not mean they must invent a document or cannot begin employment.
The employer should use the applicable official process. Errors need to be separated by type.
For incorrect pay or tax amounts, ask the previous employer to correct the details and send an amended P45. GOV.UK describes a further route through HMRC when an amended document cannot be obtained.
In practice
Real-world examples.
Example
An employee leaves one UK employer and starts with another. They give the relevant P45 information to the new payroll team, which uses it in the tax calculation process.
Example
A new starter has lost the P45. The manager initially asks the employee to obtain a replacement from the former employer.
Example
An employee spots incorrect pay figures on the document. The payroll team compares the recorded amounts with the employment records and corrects the error.
Formula
Calculation
A P45 is not a stand-alone tax calculation formula. An illustrative record check compares cumulative pay and tax on the document with the corresponding payroll records for the same employee and period.
If payroll records show $18,000 of pay and the P45 shows $17,000, the $1,000 difference requires investigation. It does not by itself tell you the tax refund or amount owed.
Do not equate total tax deducted with final liability. The individual's wider circumstances and applicable tax calculation determine that result.Case study
Seen in the real world.
Fictional case study: Rowan Services prepares a departing employee's P45, but an incorrect cumulative pay amount is entered. The employee's new payroll team flags the inconsistency. Rowan checks the relevant records, corrects the pay information, and issues the appropriate amended document.
It records the correction without distributing the employee's tax details to managers who have no payroll need to see them. The company adds a leaver-document check to its payroll controls. It also tells new starters who lack a P45 about the official starter process, reducing delay without pretending the P45 is either optional paperwork or a universal answer to every tax problem.
Watch out
Common mistakes.
- Treating a P45 as proof that final tax liability is settled. It records employment information and deductions, not every aspect of a person's tax affairs.
- Requesting a replacement for a lost document when the official guidance says to use the starter-checklist route. Distinguish loss from failure to issue.
- Sharing the whole document beyond authorized payroll needs. Its tax and personal details require appropriate handling.
Questions
People also ask.
Is a P45 used outside the UK?
This description concerns the UK PAYE document. Other countries have different employment and tax forms and processes.
What if the pay or tax figures are wrong?
Ask the previous employer to correct the details and provide an amended P45. GOV.UK describes the HMRC route if that cannot be obtained.
What if this is my first job?
GOV.UK says to fill in a starter checklist. You are not expected to have a P45 from employment that never existed.
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