Tax Reserve Calculator
Set aside a consistent percentage of your monthly business income or profit so tax bills do not become a cash-flow shock.
Choose a monthly amount, a reserve percentage and a planning period. The result is a simple savings target, not a tax calculation. A sole trader might use it against monthly income; a limited company might use it against pre-tax profit for a Corporation Tax reserve.
Choosing a starting reserve rate
The correct percentage depends on your total income, deductible expenses, business structure, VAT position and other circumstances. As a basic planning habit, many sole traders reserve a portion of every client payment, while limited companies keep Corporation Tax and VAT funds in separate savings pots. Increase the reserve when earnings rise into a higher tax band.
Check your actual position regularly. Your tax bill may also include payments on account, employer National Insurance, VAT, student loans or other liabilities. Use this tool to build cash discipline and compare it with your accountant’s calculations.
Related guides
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Information on this page is general guidance for UK small businesses and is not financial, tax or legal advice. Tax rules, allowances and product terms change. Always check current information with HMRC, Companies House or a qualified professional before making decisions.