What is RTI payroll?

What RTI replaced — and why it changed

RTI — Real Time Information — is HMRC's requirement that UK employers submit payroll data to HMRC on or before every pay date, not at year end. Every salary payment triggers a Full Payment Submission (FPS) that must reach HMRC before the employee receives their pay. If no salary is paid in a month, an Employer Payment Summary (EPS) must be filed instead. Together, the FPS and EPS are the two RTI submissions every employer makes every month without exception.

Before April 2013, employers submitted a single annual return — the P35 — at the end of each tax year. HMRC received payroll data once a year, in arrears. It had no visibility of monthly payroll accuracy until the year was over.

RTI changed that. Now HMRC receives payroll data in real time — before the money leaves the employer's account. This means tax discrepancies surface immediately, underpayments are visible monthly and HMRC can verify employee income claims against live payroll records.

• PAYE & RTI explained · UK employersWhat is RTI payroll?Real Time Information explained for UK employers — what RTI requires, what the submissions are, why the monthly timing matters and what happens when it goes wrong.Book a Free Payroll CheckView Bookd PayrollHome›What Is RTI Payroll? Direct answerRTI — Real Time Information — is HMRC's requirement that UK employers submit payroll data to HMRC on or before every pay date, not at year end. Every salary payment triggers a Full Payment Submission (FPS) that must reach HMRC before the employee receives their pay. If no salary is paid in a month, an Employer Payment Summary (EPS) must be filed instead. Together, the FPS and EPS are the two RTI submissions every employer makes every month without exception. What RTI replaced — and why it changed Before April 2013, employers submitted a single annual return — the P35 — at the end of each tax year. HMRC received payroll data once a year, in arrears. It had no visibility of monthly payroll accuracy until the year was over. RTI changed that. Now HMRC receives payroll data in real time — before the money leaves the employer's account. This means tax discrepancies surface immediately, underpayments are visible monthly and HMRC can verify employee income claims against live payroll records. For employers, the change meant the monthly payroll submission became a legal deadline, not an annual administrative task. The two RTI submissions every employer makes SubmissionWhen it is filedWhat it containsWhat happens if missedFull Payment Submission (FPS)On or before every paydayEvery employee paid: gross, tax code, deductions, YTDLate filing penalty from £100/monthEmployer Payment Summary (EPS)Any month no salary is paidScheme status, nil payment declaration, SMP/SPP recoveryHMRC assumes FPS is late — penalty triggered What an FPS contains The FPS is not just a payment notification. It is a complete payroll record for every employee paid in that run. —Employee NI number and date of birth
• —Tax code and basis (cumulative or week 1/month 1)
• —Gross pay for the period
• —Income tax deducted
• —Employee and employer National Insurance contributions
• —NI category

What an FPS contains

The RTI deadline is on or before the pay date — not after, not the following day, not the same week. If the FPS is submitted after the salary is paid, it is technically late.

For businesses managing payroll in-house through software, the FPS is often filed at the same time the payslips are processed — which is correct. The problem arises when payroll is run, salaries are paid, and the RTI submission is left as an administrative task that slips. By the time it is filed, it is late. HMRC records the filing date.

A managed payroll bureau files RTI as part of the payroll run itself — the FPS goes to HMRC before or on the payment date, every time, as a non-negotiable step in the process.

Frequently asked questions