Not just a chatbot

A tax helper that actually knows UK payslips.

Surplus reconciles every payslip and answers the tax questions you’d normally Google - grounded in your real numbers, built on genuine accountant knowledge.

Surplus reads your payslip and checks the maths - income tax, National Insurance, pension and student loan - then answers your tax questions in plain English. Built by a chartered accountant, it gives you grounded answers from your real numbers, not generic chatbot guesses.

The Payslip

Paid less than expected? You’ll know first.

Surplus reconciles every payslip against your assumptions - flags shortfalls, tracks pay changes and tells you exactly how much income to expect this month.

9:41
Spend & Income
All
Spending
Income
Transactions
Monthly Payslip
ACME LTD
MARCH 2026
Gross monthly pay£0
Standard Deductions
Income Tax
500
National Insurance
250
Pension Contribution
200
Student Loan
150
Estimated Take-home£3,100
Income Check · Action Needed
You were paid £200 less than expected.
Modelled£0
Banked£0
Home
Transactions
AI
Focus
Hub

Ask the things you’d normally Google

  • “Why was I taxed more this month?”
  • “What does a salary-sacrifice pension do to my take-home?”
  • “Is my tax code right?”
  • “How much of my pay rise will I actually keep?”

Surplus answers from a real UK-tax engine - PAYE, National Insurance, student loan and salary sacrifice - not a generic model guessing at the rules.

Surplus helps you understand your own pay and tax - it isn’t regulated tax or financial advice.

Not another budget app. Not another AI chatbot. A money copilot with a real engine underneath - built by a chartered accountant and it never makes the numbers up.

Read-only Open Banking via Yapily. Bank-grade encryption. We can’t move your money.