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Tax Pot Calculator
The January panic isn't a tax problem, it's a pot problem. Work out what % of every invoice to move to a separate account and never sweat a tax bill again.
Your numbers
2026/27 rates — check gov.uk. This is guidance, not tax advice — see disclaimer below.
Note: Class 2 National Insurance has been abolished for most sole traders — profits above the small profits threshold are treated as if Class 2 has been paid, at no cost to you, so it isn't included in the figures above.
Who this is for
Sole traders in England or Northern Ireland who invoice for their own work — trades, freelancers, consultants. If you've ever had a good year and then had a horrible January because you'd spent the tax that was sitting in your business account all along, this tool is for you.
Why put tax in a separate account instead of just remembering to save it?
Because "remembering" doesn't survive a slow month, a broken van, or Christmas. The trick that actually works is physically moving money the moment an invoice is paid — most banking apps (Starling, Monzo and others all offer this) let you create a separate "pot" or sub-account you don't touch day-to-day. Once the tax percentage is out of sight, it stops feeling like spendable cash, and the January bill becomes a formality instead of an emergency.
Making Tax Digital means I pay quarterly now, right?
No — this is the single most common MTD misunderstanding. From April 2026, qualifying sole traders have to report income and expenses to HMRC every quarter through compatible software. Payment is still due on the normal self-assessment dates (31 January, plus payments on account where they apply) — quarterly updates don't change when tax is actually paid. If you're not sure whether MTD applies to you yet, run our MTD Ready Checker.
What if I end up earning less than I expected?
Then you've simply over-saved, which is a good problem to have — the spare pot rolls into next year's tax, covers a payment on account, or just sits as a buffer. It's a far better outcome than under-saving and having to find a lump sum you don't have. Revisit this calculator whenever your turnover forecast changes significantly through the year.
Please note: this tool gives a guide or estimate only. It may not be 100% accurate and is not professional advice — always check the figures before you rely on them. Rates, thresholds, allowances and rules can change without notice and may be out of date by the time you use this tool. Verify against HMRC / GOV.UK or your accountant before acting.
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