How do I authorise an agent for Making Tax Digital for Income Tax?

Your agent sends you a link from their HMRC agent services account. You sign in with your own HMRC details and accept it within 21 days. If you start MTD in April 2027, do this well before 7 August 2027.

Authorising an agent is how you let an accountant, bookkeeper or managed service deal with HMRC about Making Tax Digital for Income Tax (MTD) for you. HMRC calls it a digital handshake. There is no paper form and you never share your password. This page follows GOV.UK as checked on 15 October 2026.

Main or supporting agent

You can have one main agent and any number of supporting agents.

A bookkeeper who only sends your updates can be a supporting agent. Whoever sends your tax return needs to be your main agent, unless you send it yourself.

How the request works

1. Your agent selects Ask a client to authorise you in their agent services account. GOV.UK says they may need details such as your National Insurance number, date of birth and tax reference.
2. They email you the link.
3. You select it and sign in with the sign-in details you use for that tax service. If you have more than one account, use the right one. If you have none, you can create them from the link.
4. You may be asked to verify your identity.
5. You accept the request. The link expires after 21 days, and the agent sends a new one if it does.

GOV.UK is plain about passwords: "You must not give your sign in credentials to your agent or anyone else."

If you already have an agent for Self Assessment

Many people already have an accountant who files their tax return. GOV.UK says that agent can add their existing Self Assessment authorisations for MTD, and HMRC then treats them as your main agent. You may not need to accept a new link. But adding an authorisation does not sign you up. The agent still has to do that as a separate step.

What this means for you

If you start on 6 April 2027, the order is: authorise your agent, then they sign you up for the 2027-28 tax year, then they send your first update. That update covers 6 April to 5 July 2027 and is due by 7 August 2027. At the Budget on 28 October 2026 the government said people who must join in April 2027 will get no penalty points for late 2027-28 quarterly updates either, though the updates must still be sent. For you, the earliest a late update can earn a point is 7 August 2028. Still leave time for the handshake and sign-up.

To sign you up, the agent will need your full name, date of birth and National Insurance number. Sole traders also give the business name, address and type of work. For any business or let that started in the last 2 tax years, they need the start date.

Steps to authorise an agent

1. Choose who will act for you and agree whether they are your main or supporting agent.
2. Check they have an HMRC agent services account, which they need to sign you up.
3. Ask whether they can use your existing Self Assessment authorisation, if they already file your return.
4. If not, give them the details they ask for so they can send a request.
5. Open the link in their email, sign in with your own HMRC details and accept within 21 days.
6. Ask them to confirm when they have signed you up and which tax year you start.
7. Put 7 August 2027 in your diary and check after each deadline that the update has gone.

Changing or removing an agent

You can remove an agent at any time using the Manage your tax agent or Manage who can deal with HMRC option in your personal or business tax account. If you choose a different main agent, the previous one loses access. Agents can also cancel an authorisation from their side.

Not sure when you start? The free MTD check shows your date. There are more guides in the trades section and the landlord section.