Self Assessment sounds complicated. It isn't, once you know what it actually is. HMRC does a spectacular job of presenting it as if it might be.

If you tattoo for a living and work for yourself, you need to file one every year. This is how the self-employed pay tax in the UK. There's no employer deducting anything from a wage, so HMRC asks you to report what you earned, subtract what you spent running your business, and pay tax on what's left. That's the whole system. The form is just the mechanism.

Registering with HMRC

Before you can file, you need to tell HMRC you're self-employed. You do this online through your Government Gateway account.

If you've been tattooing for a while and haven't registered yet, you're late. Register anyway. Late registration gets a small penalty; years of ignoring it gets considerably worse. The deadline is 5 October after the end of your first tax year trading. If you started working for yourself in the 2023/24 tax year, the registration deadline was 5 October 2024.

Once registered, HMRC issues you a Unique Taxpayer Reference — a 10-digit number you'll use for every return going forward.

What the tax year covers

The UK tax year runs from 6 April to 5 April the following year. Your Self Assessment return covers all your income and expenses across that period. The 2024/25 return covers 6 April 2024 to 5 April 2025.

What to gather before you file

You'll need:

The expenses part is where most tattoo artists lose money. If you've been guessing at what counts, you'll underclaim every year. More on this below.

How to file

Log in to your Government Gateway account and work through the Self Assessment return. It's laid out in sections — income, expenses, and a few other areas depending on your circumstances. The online version is more straightforward than it sounds on paper.

The filing deadline is 31 January. That covers the tax year that ended the previous April, so your 2023/24 return needed to be filed by 31 January 2025. Miss it and you get an automatic £100 penalty, which goes up the longer it's ignored.

File early if you can. There's no benefit to waiting until January, and doing it in April or May means you know exactly what you owe months before it's due.

What you'll actually owe

Once you've submitted, HMRC calculates your bill based on your figures. You'll pay Income Tax on profits above the Personal Allowance (currently £12,570), plus Class 4 National Insurance on profits above a lower threshold.

First-time filers often hit something unexpected: Payment on Account. If your tax bill comes in above £1,000, HMRC asks for half of next year's expected bill at the same time. It's not a penalty. It's just how the system manages cash flow across the year. But if no one warned you, your January bill can be 150% of what you budgeted for.

Saving a percentage of every payment you receive — 25–30% is a reasonable rule of thumb for most tattoo artists — means this is never a shock.

The expenses most tattoo artists miss

Ink and needles, most people think to claim. The bigger picture is less obvious.

The machine you bought secondhand. Stencil paper and transfer solution. Sterilisation supplies and sharps disposal. The table you used at a guest spot. Convention entry fees, hotel costs, travel to and from bookings. Subscriptions to design or reference apps. Training courses. Insurance.

There's also the question of your workspace. If you work from a home studio, a proportion of your household bills — heating, electricity, broadband — is claimable. If you rent a chair at a studio, that rental fee comes off your profit in full.

Each of these sounds small on its own. Across a full year they add up to a meaningful difference in your tax bill.

What people get wrong

Keeping no records during the year. HMRC can open an enquiry up to four years after filing. A weekly log of income and a folder of receipts is enough for most sole traders. Don't leave everything to January.

Not declaring cash. Cash payments are taxable income. "It was cash" doesn't hold up under enquiry.

Missing the Payment on Account step. Knowing it's coming and setting money aside throughout the year makes January manageable. Finding out about it when you open the bill does not.

Get the complete guide

This covers the shape of how Self Assessment works for tattoo artists. For a full step-by-step walkthrough — including what to register, how to file, a complete breakdown of every claimable expense, and how to save for your bill throughout the year — that's what the Tattoo Artist Bundle covers.

It's the UK Self-Employment Tax Guide plus a tattoo-specific add-on, written for someone with no accounting background. One-off purchase, instant PDF download.