How to calculate self-employed tax

Self-employed tax is charged on profit, not turnover. Deduct allowable business expenses from your income, then apply income tax plus self-employed social contributions to what remains — and remember you may also owe payments on account towards next year.

The rule

Tax due = (turnover − allowable expenses) taxed at income tax bands + self-employed social contributions

Do it automatically — Self-employed / freelancer tax

Step by step

  1. 1Total your invoiced income for the tax year.
  2. 2Subtract allowable expenses: equipment, software, travel, home-office share, professional fees.
  3. 3Apply income tax bands to the resulting profit.
  4. 4Add self-employment social contributions, then check whether advance payments on account apply.

What trips people up

  • Set aside roughly 25–35% of every payment received so the bill is never a surprise.
  • Your first year can bring a bill of 150% of the tax due once payments on account start.

Common questions

Can I deduct my home office?

Yes — either a flat rate per month or a fair proportion of household running costs.

Do I need to register for VAT or sales tax?

Only once you pass the registration threshold, though voluntary registration can suit B2B businesses.

Skip the maths

Income tax, NI/PRSI/SE tax and payments-on-account from your annual profit.

Open the sole trader & 1099 tool

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