Earning on the side? Know where you stand with HMRC.
A job in the day and something of your own in the evenings. Fenquist keeps the side income separate and tells you, roughly, what it adds to your tax bill on top of your salary.
What gets in the way, and what helps
Not sure if you even need to tell HMRC.
The estimate shows whether income is under the £1,000 trading allowance, and uses it automatically when that's better.
Salary already uses up your tax-free allowance.
Add your other income and the estimate shows only the extra tax the side income adds.
Friends and followers paying in five different ways.
Send a payment link anywhere, including in a message or a bio, and see every payment in one list.
Before your side income grows
- Under £1,000 a year of trading income (before costs) is usually covered by the trading allowance.
- Above it, you'll need to register for Self Assessment and report the profit.
- Online platforms now report sellers' income to HMRC, so keep your own records to match.
- Check your employment contract allows outside work, especially for similar clients.
General information, correct as of October 2026, not tax or legal advice. Check GOV.UK or an accountant for your own situation.
Questions
Is Fenquist free for a small side income?
The free plan covers up to 5 clients, unlimited invoices, payment links and the tax estimate. Pro adds automatic reminders and unlimited clients when you need them.
Does the estimate include my job?
Only if you enter your salary. It's assumed to be taxed already through PAYE; the estimate shows the extra your business adds.