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Signing up with HMRC

What you need, the step-by-step, identity checks, and how accountants fit in.

4 min read

Signing up for MTD is a separate step from just "using MTD software". It tells HMRC that you (or your agent) will be submitting through MTD for a specific tax year, and it authorises your software to talk to HMRC on your behalf.

You don't have to sign up months in advance. You do have to sign up before your first quarterly update is due.

Who does the signing up

Three common patterns:

  1. You sign yourself up. You log in to HMRC using your Government Gateway ID, tell HMRC what active sole-trade and/or property income you have, and authorise your software.
  2. Your accountant signs you up as your agent. They use their agent services account, request authorisation from you, and then register you in the MTD service.
  3. Your software walks you through it. Most MTD software prompts you through the sign-up as part of the initial setup.

If you use Kite, we walk you through it inside the app. You never leave our flow unless HMRC's identity check needs extra verification.

What you'll need before you start

  • Your Government Gateway user ID and password. This is the same one you use for Self Assessment. If you've forgotten it, recover access before you start the sign-up, HMRC has a "forgotten username/password" route, but it can take a few days.
  • Your National Insurance number (format: XX 12 34 56 X).
  • Details of your active sole-trade businesses (name, start date, description of what you do).
  • Details of your property income, UK residential, UK commercial, or foreign, as applicable.
  • A photo ID (passport, driving licence, or similar) and a phone with a camera. HMRC sometimes asks for face-match identity verification during sign-up.

Step-by-step

1. Get your software set up and connected to HMRC

Open your software account. Somewhere in the onboarding you'll see a "Connect to HMRC" or "Authorise HMRC" button. This opens a browser window to GOV.UK where you sign in and grant the software permission to submit on your behalf. The permission is scoped and revocable at any time from your HMRC account.

2. Tell HMRC what income you have

In the sign-up screens (or in your software if it's built in):

  • Add each active sole-trade business.
  • Add your property income (if any).

If you have something you're not sure about, a tiny amount of hobby income, or a sublet that you haven't previously declared, now is a good moment to sort it out, not a bad one.

3. Confirm your identity

HMRC may ask you to verify who you are:

  • Face match: take a photo of your face and a photo of your passport or driving licence using your phone. Their system compares them.
  • Knowledge-based questions: HMRC asks you a few questions about information they already hold (previous addresses, tax return figures, etc.).

Some people sail through; others get stuck. If you hit an identity check problem, contact HMRC's help line rather than guessing, guessing can lock you out temporarily.

4. Confirm your accounting period

Tell HMRC (via your software) whether you're using standard quarters (6 April – 5 July, etc.) or calendar quarters (ending on the last day of the month). Standard is fine for most people. Your choice locks in for the tax year. See Key dates.

5. Done

Once you're signed up, HMRC records your MTD obligations, you'll see your quarterly update deadlines listed in your account. Your software mirrors them so you know what's coming.

Do I still have to file a Self Assessment for last year?

Yes. You file a normal Self Assessment for the tax year before you enter MTD. For someone starting MTD on 6 April 2026, that means filing 2025-26 the usual way, by 31 January 2027.

After that, the "Self Assessment tax return" is replaced by your MTD quarterly updates and final declaration.

Can I sign up voluntarily, before I'm required to?

Yes. HMRC has run a voluntary pilot since April 2025. You can join early to get comfortable before being mandated. Two things to know:

  • The voluntary regime has slightly different penalty thresholds (see Penalties). In practice HMRC has said they won't penalise quarterly updates in the pilot, but the final declaration has points. Check the current rules before opting in.
  • Once you sign up, you're in for the rest of that tax year and onwards. You can leave in limited circumstances, but don't sign up voluntarily on a whim.

If you'd rather practise without being officially signed up with HMRC, most software has a "sandbox" or "dry-run" mode you can use, Kite does.

Frequently asked setup questions

Do I need a new Government Gateway ID? No. Use the same one you use for Self Assessment. Don't create a second one, you'll just confuse yourself and HMRC.

Do I need a UTR? Your UTR (10-digit Unique Taxpayer Reference) is already tied to your account. MTD's systems use your National Insurance number as the primary identifier, so you generally don't type your UTR in anywhere.

Can I sign up before the pilot if I'm a new business? New businesses are only brought into MTD from the April following the first Self Assessment they file. If you start trading in 2026-27, you'll file your first Self Assessment by 31 January 2028; if your 2026-27 income puts you over the threshold, you'd enter MTD from April 2027. In the meantime you can use MTD-style software anyway to get used to the workflow.

Does my spouse need to sign up separately? Yes, MTD is per individual. If you jointly own a rental property, you each sign up separately (or together if you're below the threshold). See For landlords for the joint-property simplifications.

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