afterax

UK tax guides · 2026/27

Plain-English UK tax, written carefully.

Long-form explainers built around the Afterax calculators. Every guide is reviewed against current HMRC rates and rewritten when they change.

How to use these guides

The guides are written for decisions where a calculator result needs context: whether a pension contribution changes your marginal rate, why a salary increase does not arrive as the same amount of take-home pay, or when an allowance is being tapered away. Start with the guide that matches the tax rule you are trying to understand, then open the linked calculator with your own income, region, pension and student loan details.

Each article focuses on the practical assumptions behind the result rather than generic tax commentary. Where a threshold depends on adjusted net income, household rules, Scottish bands or company-profit calculations, the guide calls that out so you know which inputs to change. For a quick scan across several thresholds, use the tax cliff map; for a precise number, use the relevant calculator after reading the explanation.

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UK Tax Cliff Map 2026/27

A source-backed map of the income thresholds where tax bands, allowances, childcare support and pension rules change.

Open the map

Income tax

6 min read

The 60% tax trap, explained

Why earning between £100k and £125k costs you 60p of every extra pound, and how to escape it.

Read the guide

Pension

7 min read

Is salary sacrifice worth it?

How a £1 of take-home turns into £2 or £3 in your pension, and the trade-offs nobody mentions.

Read the guide

Investing

7 min read

Capital gains tax on shares

When you owe, how much, and the wrappers and tricks that change the answer.

Read the guide

Income tax

5 min read

What does tax code 1257L mean?

Decoding the UK's standard tax code: what each digit and letter does, and the codes that quietly cost you money.

Read the guide

Family

6 min read

High Income Child Benefit Charge, explained

Why earning £60k+ can claw back your child benefit, what the £80k cliff is, and the pension move that erases it.

Read the guide

Business

8 min read

Director salary vs dividends in 2026/27

The post-Budget take-home maths for limited-company owners, with a 2026/27 worked example.

Read the guide

More guides coming. Got a topic to suggest? Get in touch.