Estimate your Self Assessment bill for 2026/27. Your tax is based on your profit — income minus expenses — plus Class 4 National Insurance.
If your bill is over £1,000, HMRC also asks for payments on account towards next year — see the payment on account calculator for those.
On your profit — income minus allowable expenses. You pay income tax above your personal allowance, plus Class 4 National Insurance on profit above the threshold.
Costs incurred wholly for your work — tools, materials, travel, phone, insurance and more. Keeping them recorded reduces your taxable profit.
From April 2026, if your gross self-employment and property income combined is over £50,000 (£30,000 from 2027, £20,000 from 2028) you must keep digital records and file quarterly.
Loading the calculator…