How we research and update our guides

Last updated 30 October 2026

Tax content has to be right. This page explains where our facts come from, how our numbers are worked out and what happens when the rules change.

Where the facts come from

• Rules, thresholds and deadlines come from HMRC guidance on GOV.UK, mainly Find out if and when you need to use Making Tax Digital for Income Tax and the related pages on quarterly updates, penalties and digital records. Each guide lists the GOV.UK pages it relies on under “Sources”.
• Tax rates and allowances used in the worked examples come from GOV.UK’s published rates for the tax year shown.
• Accountant price ranges come from price lists that UK practices and online accountants publish on their own websites. We show a range, the month we last checked it, and never a single “average” we cannot source.
• The accountant directory uses Companies House’s free company data (Open Government Licence v3.0) and postcode locations from postcodes.io (OS, Royal Mail and ONS data). We refresh it monthly.

We do not use forum posts, social media or other comparison sites as a source for a rule.

How the numbers are worked out

• “Am I affected?” compares your qualifying income – self-employed turnover plus rent received, before costs – with HMRC’s thresholds for each tax year.
• Worked examples use illustrative figures for each trade, not real people. Tax estimates use England, Wales and Northern Ireland income tax bands, the standard personal allowance and Class 4 National Insurance for the year stated, and assume no other income. Scotland has different bands. They are a rough guide to how much to set aside, not a tax calculation.

Checking and updating

• Every guide shows the date it was last updated. We re-check the rules after each Budget and fiscal event, and whenever HMRC changes its MTD guidance.
• When the rules change, we update every affected page on the same day where we can, and change the date shown on it.
• We are arranging an independent review of our guides by a qualified UK accountant. When it is done, each reviewed guide will show the reviewer’s name and professional body.

Corrections

If you spot something wrong or out of date, email [email protected] with the page address. We check every report against GOV.UK and fix confirmed mistakes as quickly as we can.

Independence

Accountancy practices pay us for introductions, but they have no say over what our guides say. See about us for how we are paid.