How to register as a sole trader — and the five things nobody tells you

The registration itself is almost an anticlimax: tell HMRC you're self-employed by registering for Self Assessment, get your UTR, done. Free, online, ten minutes. Here's the process — and the five things that actually matter, which nobody mentions at the time.

The formal bit

• Deadline: register by 5 October after the end of the tax year in which you started. Started trading in July 2026 (tax year 2026/27)? Register by 5 October 2027 — though sooner is better for everything downstream.
• How: HMRC online — "register for Self Assessment as self-employed". You'll get a UTR (keep it forever) and, later, a reminder to file your first return.
• Name: trade under your own name or a business name — no registration needed for the name itself, just don't use ltd/LLP or a protected word, and check no one has trademarked it.

The five things nobody tells you

1. Open a separate account the same week. Mixing money is the single decision people most regret by year two. A Mettle account is free and takes minutes.
2. Start the tax pot immediately. Move ~20% of every payment received into a separate pot from payment one. Your first bill can be 18 months away — with payments on account making it 150% of what you'd guess. Future you will be very grateful.
3. Capture expenses from day zero — including costs from before you registered, which are generally claimable. Receipts into an app, three seconds each, and your first return shrinks properly.
4. Check your insurance, not just your tax. Public liability (if you're near other humans or their property) and professional indemnity (if you advise) — often required by clients, always cheaper than a claim.
5. Know the thresholds you're heading towards: £50,270 (higher-rate tax), £90,000 rolling (VAT registration — see the trap of not watching this monthly), and the MTD income steps (£50k now, £30k from 2027, £20k from 2028).

Or compress all five into one move: our Start package is £19 + VAT a month — FreeAgent, Self Assessment and a named accountant, from your first week of trading. Get started.