The Master Guide.

RotaPayPro is built to handle highly complex employment contracts. To get accurate payslip predictions, you must first configure your core settings correctly.

Choosing Your Pay Basis

Tax Codes & NI Categories

Your tax code is the engine's most vital input. Enter your exact HMRC tax code (e.g., 1257L, BR, S1257L, or K490). RotaPayPro natively understands:

• Scottish Tax Bands: Simply ensure your code starts with an "S". The engine will automatically apply the Scottish 6-band tax system (Starter, Basic, Intermediate, Higher, Advanced, Top).
• K-Codes: Handled natively as negative allowances.
• Non-Cumulative (W1/M1): If your code ends in W1, M1, or X, check the "Non-Cumulative" box in settings. The engine will stop looking at your Year-To-Date (YTD) earnings and calculate tax on a strict month-by-month basis.

Logging overtime is simple, but the mathematics behind it are forensic. When you log an overtime shift, the engine processes it through our "Smart Buffer" algorithm.

The Part-Time Overtime Buffer

In the UK, if you are contracted to 20 hours a week, but the full-time threshold is 37.5 hours, you are generally not legally entitled to "Time and a Half" (1.5x) until you cross that 37.5-hour threshold.

If you enable Smart Overtime in Settings, RotaPayPro calculates this exactly:

1. It calculates the monthly "gap" between your contract and full-time hours.
2. Any overtime logged within this gap is automatically paid at your 1.0x Basic Rate (Additional Basic Hours).
3. The moment you cross the threshold, the app automatically upgrades the remaining overtime hours to your configured Premium Rate (e.g., 1.5x).

Standby & Recalls

If you work on-call, you can configure custom "Standby" fees (either a flat rate per shift or an hourly retaining fee). If you are called into work while on standby, simply log a "Recall to Duty" inside that shift. The engine will stack your recall premium on top of your standby allowance flawlessly.

True Cumulative Tax

RotaPayPro doesn't guess your tax. It uses a True Cumulative Engine. This means your tax for Month 5 is calculated by looking at your total earnings for the year so far, calculating the total tax due for the year, and subtracting the tax you already paid in Months 1-4. To keep this accurate, you must update your "Previous Taxable Pay YTD" and "Tax Paid YTD" in settings after every official payday.

£100k+ Allowance Tapering

For high earners, the engine automatically detects if your projected annual income exceeds £100,000. It will automatically taper your Personal Allowance (reducing it by £1 for every £2 earned over £100k) to ensure your payslip remains perfectly accurate.

The Leave Dashboard is designed to protect your employment record and manage your time off efficiently.

The Bradford Factor

Many UK employers use the Bradford Factor to measure employee absence. It penalizes frequent, short absences much more harshly than infrequent, long absences. The formula is S² × D (Spells squared × Total Days).

RotaPayPro automatically calculates your Bradford Factor score based on the sick leave you log. It provides a visual safety gauge so you always know where you stand with HR.

Time Off In Lieu (TOIL)

If your company allows you to bank overtime hours instead of being paid for them, you can configure the TOIL engine. You can set the app to:

• Always Bank TOIL: Every overtime hour logged goes into your TOIL balance instead of your payslip.
• Employee Choice: Overtime is paid normally, UNLESS you add the note #TOIL to the shift. The engine will instantly remove the pay from your payslip and credit it to your leave balance.