What a payroll user must see

A) Per-employee (for a given pay period / month)

Identity & setup

• Name, address (optional on screen), NI number, Tax code, NI category letter, starter/leaver flags. GOV.UK+1Rapid Formations

• Student loan plan & postgraduate loan flags; auto-enrolment status (active/opt-out), pension scheme name & contribution rates. GOV.UKRemote

Timesheet → pay lines

• Approved hours by type: basic, overtime, night, holiday, sickness (SSP), parental (SMP/SPP/SAP/ShPP), unpaid leave.

• Gross pay split by rate (e.g., base, night allowance, role bonus), unpaid breaks deducted, overtime premium, holiday pay hours. Payslips must show gross and the hours when pay varies by time worked. GOV.UKGOV.UK AssetsLow Incomes Tax Reform Group

Deductions & additions

• Employee PAYE income tax, Employee NI, employee pension, student loan, postgrad loan, AEOs (if any).

• Employer NI, employer pension (for cost-to-employer view). GOV.UK

Totals & audit

• Net pay, Taxable pay, NI-able pay, Pensionable pay, YTD for each, and a per-shift audit trail (approved minutes, break rule applied, rounding, overtime rule).

• “Payslip preview” panel with: gross, itemised deductions, net, and (if variable hours) the hour totals—this is a legal must. GOV.UK+1

B) Company/month (pay run dashboard)

• Headcount paid, Gross pay total, PAYE income tax total, Employee NI, Employer NI, Employee pension, Employer pension, Student/Postgrad loan totals, Net pay total, Total employer cost.

• RTI queue: each employee’s FPS line status; EPS needs (e.g., statutory recovery, NICs holiday, apprentices, “no payments this tax month”). FPS must be sent on or before payday; EPS by the 19th of the following tax month. GOV.UK+1

• P32-style month summary (Employer Payment Record): PAYE due = FPS liabilities minus EPS reductions; helps reconcile what you pay HMRC by the 22nd (electronic). Moore Kingston Smith

• Compliance banner: PAYE reference, Accounts Office ref, tax month number, payment deadline hints. GOV.UK

What must be on a payslip (map your UI to this)

• Gross pay, each deduction (variable ones itemised), net pay, and number of hours when pay varies by time worked; NI no. and tax code can be shown (not mandatory but common/best-practice). Your payslip preview and employee pay screen should reflect this exactly. GOV.UK+1

HMRC reporting you need to satisfy (RTI)

• FPS (per pay run): employee pay, tax, NI, tax code, starter/leaver, etc. Send on or before payday (use contractual payday if paid early e.g. for bank holidays). Surface “FPS payload preview” in your UI. GOV.UK+1

• EPS (monthly if needed): reclaim/adjustments (e.g., statutory payments recoveries, CIS deductions, Employment Allowance). Send by the 19th of the following tax month. Show an EPS “adjustments” panel. GOV.UK

• Keep payroll records (pay, deductions, reports) for at least 3 years—build an export/download area. GOV.UK Assets

NI categories & student loans (store & show)

• Show the NI letter (A, B, C, H, J, M, Z…) and make it editable by payroll staff—with a small helper tooltip. It drives NI rates. Show student loan plan type and postgrad loan flags in the sidebar of the employee pay view. Rapid Formations

Pension auto-enrolment (must track)

• Flag each employee’s assessment status, pensionable pay, and contributions. Keep an export for your scheme provider and show the contribution schedule in the run. Remote

Screens I recommend (so you can implement fast)

1) HR ▸ Payroll ▸ Run overview (Month)

Tiles: Gross | PAYE | EE NI | ER NI | EE Pension | ER Pension | Loans | Net | Employer Cost.Table (employees): Name, NI no., Tax code, NI cat, Approved hours, Overtime hrs, Gross, PAYE, EE NI, ER NI, EE Pen, ER Pen, Loans, Net, RTI status (FPS ✓/✗).Footer: P32 totals + link to “Prepare EPS” (if any recovery/allowance applies). Moore Kingston Smith

2) HR ▸ Payroll ▸ Employee pay (Month)

Left: personal + setup (NI no., tax code, NI cat, loans, pension scheme).Middle: Timesheet breakdown (per day/shift) → basic hrs, OT hrs, night hrs, break mins, holiday hrs; bonus lines (e.g., Forklift hourly, Night allowance) → show amount and rule source.Right: Deductions (PAYE, EE NI, loans, EE pension), Employer costs (ER NI, ER pension), Payslip preview and FPS preview.Bottom: Audit flags from your reconciler (edge rounding, break rule applied, overtime mode, policy sources). (This matches the flags you already write.)

3) HR ▸ Payroll ▸ RTI submissions

• FPS queue with validation: missing NI no., invalid tax code, zero net pay checks, leaver markers, etc.

• EPS form (month): tick boxes for statutory recovery/compensation or “No employees paid” declaration.

• Log with timestamps and HMRC receipt IDs. (For actual sending, either integrate an HMRC-recognised gateway or export payload and submit via recognised software.) GOV.UKLow Incomes Tax Reform Group

Connecting to HMRC (realistic options)

• HMRC requires RTI-compatible software. Either:

1.  **Use an HMRC-recognised payroll gateway** (Sage, Xero, Rippling, PayCaptain, etc.) and feed it from your app via API/file, **or**

2.  Build a full RTI client using HMRC’s specs and go through recognition (heavy).Your UI can still own timesheets, gross-to-net, and provide an **“Export FPS/EPS”** to a recognised system. [www.rossmartin.co.uk](https://www.rossmartin.co.uk/sme-tax-news/7507-hmrc-recognised-payroll-software?utm_source=chatgpt.com)[Low Incomes Tax Reform Group](https://www.litrg.org.uk/employers/reporting-paye-real-time/real-time-information-rti-software-getting-started?utm_source=chatgpt.com)

Minimal data you should store (if not already)

• Per employee: ni_number, tax_code, ni_category, student_loan_plan, postgraduate_loan:boolean, pension_scheme_id, pension_enrolment_state, pension_rates, starter/leaver dates.

• Per pay run line: taxable_pay, niable_pay, pensionable_pay, ee_tax, ee_ni, er_ni, ee_pension, er_pension, student_loan, pgl_loan, net_pay, ytd mirrors.

• Settings: PAYE reference, Accounts Office ref, RTI contact, pay frequencies, tax month mapping.

How your Timesheet → Payroll mapping should work

• Approved minutes (minus unpaid breaks) → basic hours at base rate.

• Overtime minutes → OT rate (or multiplier) lines.

• Night minutes → separate rate lines (your Night Allowance bonus).

• Holiday/SSP/etc. → separate statutory lines.

• Roll these into gross pay, then compute statutory deductions → net pay; show employer NI/pension in the cost panel. (Payslip must itemise gross, deductions, net—plus hours for variable pay.) GOV.UK