The HMRC have today launched the registration for their new Tax Advisor agent services accounts which are becoming a mandatory requirement for professionals to continue interacting with HMRC if they are being paid to do so.

The portal is open to registration from 18th May 2026.

This is to replace the existing agent services registration process. If you already have an agent services account (“ASA”), you will not need to register again. You can check whether you need to register for new ASA portal here:
Does your business provide tax services? – Guidance – GOV.UK

Who needs to register?
HMRC has issued guidance which states:
“If you interact with HMRC about someone else’s tax affairs and get paid for it, we consider you to be a tax adviser. This means you’ll need to register for an agent services account.

Interaction with HMRC includes:
– phone, post or email
– messages through the GOV.UK website or HMRC app
– sending returns, claims or other documents

The legal entity that interacts with HMRC must register. Individual employees will not need to register separately, but we’ll need to carry out checks on certain people within your business.”

On this basis, the new registration requirement applies to any deputies who receive renumeration for their time and need to interact with HMRC, even if they do not consider themselves to be tax advisors.

This includes both professional and potentially local authority deputies who receive renumeration for general management under Court of Protection Practice Direction 19B. The registration however will be at firm level and there is no registration fee.

The registration portal opens on 18th May 2026 and the link to register can be found here:

How to register
To register for the new Agent Services Account you can do so here: https://www.gov.uk/guidance/apply-for-an-agent-services-account

Once registered, the company will be able to create a Government Gateway user ID for each member of staff.

To register, the company will need to provide:
– your Government Gateway user ID and password (you can create these on the sign-in page if you do not have them)
– the Unique Taxpayer Reference (UTR) for your tax adviser firm
– the postcode associated with your UTR
– your company registration number (if you have one)
– your VAT registration number (if you have one)
– the name of your anti-money laundering supervisory body and evidence of your supervision
– the names and contact details of any relevant individuals working for the business registering

Deadlines for Registration
You’ll have 3 months from the date you need to register to apply for an agent services account. You can continue to interact with HMRC on behalf of your clients during these 3 months and while they consider your registration.

You’ll need to register for an agent services account from 18 May 2026, unless one of the following applies:
– if you already have a Self Assessment or Corporation Tax account, you’ll need to register from 18 August 2026
– if you only provide third-party payroll services on behalf of clients and do not interact with HMRC in any other way, you’ll need to register from 18 November 2026
– if you are a financial services organisation, you’ll need to register from 31 December 2026

Registration is now open and you can do so at anytime before the above deadlines should you wish.