MoneyCalcs UK Guides
Plain-English guides to the rules and concepts behind our calculators.
MoneyCalcs UK guides
Each calculator page includes a written explanation of the rules it applies, the assumptions it makes and the official sources it relies on. These are the most useful starting points.
- How much tax do I pay self-employed in the UK?How Income Tax and Class 4 National Insurance are worked out on your profit, with worked examples.Read
- Why is my first Self Assessment tax bill so high?Payments on account explained, and why a first January payment can be around 150% of the tax for the year.Read
- Making Tax Digital for Income Tax: what sole traders need to know in 2026Qualifying income, the £50,000, £30,000 and £20,000 thresholds, digital records and quarterly updates in plain English.Read
- Companies House identity verification for directors & PSCs: 2026 guideWho has to verify, how the transition period works, why director and PSC timing differ, and how to check your own dates.Read
- How much should I save before maternity leave?A simple way to work out your savings gap from your maternity pay, costs and planned leave length.Read
- Maternity pay on a £30k, £40k or £50k salaryIllustrative Statutory Maternity Pay examples for three common salaries, and why your own figure may differ.Read
Start with a calculator instead
The calculators are the quickest way to get a figure, and each one explains how the result is worked out.