Setting up as a tax agent

What do you need to consider when setting up as a tax agent? What are the steps? How do you register with HMRC?

This is a freeview ‘At a glance’ guide to setting up as a tax agent.

This guide works through the key regulatory and compliance steps new professional tax agents should take, points they need to consider and things that they need to be aware of, as well as how to register with HMRC.

Professional body requirements and best practice

If you are already a member of a professional bookkeeping, accounting or tax body, you will need to comply with their specific regulatory requirements.

The rules differ between professional bodies, but requirements normally include:

  • Holding a practising certificate: this authorises you to provide certain services.
  • Having Professional Indemnity Insurance (PII).
  • Issuing clients with a letter of engagement, setting out the scope of your services.
  • Keeping yourself up-to-date via Continuing Professional Development (CPD).

If you are not a member of a professional body, you should still consider whether any of the requirements set by such organisations would benefit you. This can be important in Protecting yourself from negligence claims.

In running a practice of any kind, you will need other forms of insurance, as well as PII, such as public liability insurance and employer’s liability insurance. If you use your car for business travel, that insurance policy may need amending too.

Anti-Money Laundering supervision

Tax agents must register for Anti-Money Laundering (AML) supervision.

  • If you are a member of a professional body, this is done through membership. The body must be a recognised supervisory body such as the Institute of Chartered Accountants in England and Wales (ICAEW), the Association of Chartered Certified Accountants (ACCA), the Chartered Institute of Taxation CIOT or the Association of Accounting Technicians (AAT). 
  • If you are not a member of a supervisory body for AML, registration with HMRC can take up to 45 days.

Anti-Money Laundering checks

  • You are required to undertake Anti-Money Laundering checks when you take on clients.

General Data Protection Regulation and the Information Commissioner’s Office

  • As you are almost certainly holding information of private individuals, you need to comply with the General Data Protection Regulation (GDPR).
  • You will need to register and pay an annual data protection fee to the Information Commissioner’s Office (ICO).

Register your own business with HMRC for tax

Technical resources

You should consider what technical resources and reference materials you will need when running your business, both to advise clients on their affairs and as part of your Ongoing CPD.

You may wish to seek specialist advice or support from a technical support service such as Virtual Tax Partner. 

Professional Conduct in Relation to Taxation

The Professional Conduct in Relation to Taxation (PCRT) adopted by the main professional accounting and tax bodies, sets out the professional standards expected of a member when undertaking tax work.

Even if you are not a member of a professional body, this guidance is useful to all tax agents.

HMRC’s agent standards

HMRC’s ‘standards for agents’ set out what HMRC expect from tax agents.

Business premises

Many tax advisers start their practices from home. This can result in specific considerations, such as:

  • Would running a business from home be in breach of any tenancy agreement?
  • Is permission needed from a mortgage provider, local planning office or council?
  • Will Business Rates be payable (rather than Council Tax) on the part of the property used for the business?

Registering as an agent with HMRC

From 18 May 2026, all tax advisers who interact with HMRC are required to register with HMRC.  

'Interaction with HMRC' includes:

  • Contacting HMRC by phone, post or email.
  • Using the HMRC online webchat pr internet portal.
  • Filing a return, claim, notice or other document with HMRC.
  • Communicating with HMRC in any other way.
  • See Mandatory tax adviser registration with HMRC

To register for mandatory tax advisor registration, all advisers will need an Agent Services Account (ASA). 

  • HMRC have advised that from 18 May 2026, they will introduce a new online registration system for ASAs.   
  • For advisers who meet the conditions for mandatory registration but do not currently have an ASA, they will be required to apply for one.  
  • Registration will take place in stages.
    • Exactly when an adviser has to register will depend on their circumstances. 

HMRC have confirmed that agents who already have an ASA will still need to register, but the process is expected to be 'lighter' and involve a transition to move their existing account across to the new registration platform. 

  • HMRC will contact these agents through their ASA.
  • Agents should therefore check that contact details in their ASA are up-to-date. 

When to register

Tax advisers will need to register for an ASA from 18 May 2026, unless one of the following applies: 

  • The tax adviser already has a Self Assessment account or Corporation Tax account, in which case registration will be from 18 August 2026. 
  • If the tax adviser only provides third-party payroll services on behalf of clients and does not interact with HMRC in any other way, registration will take place from 18 November 2026. 

Even if advisers are not required to register until one of the later dates, they can still use the online registration service from 18 May 2026. 

The registration period

Tax advisers will have three months from the date they need to register to apply for an agent account.  

  • During these three months, the adviser can continue to interact with HMRC whilst HMRC considers the application. 

What happens if an adviser fails to register

If an adviser meets the conditions for mandatory registration but fails to register for an ASA, HMRC may: 

  • Issue a formal notice asking the adviser to stop acting. 
  • Temporarily or permanently ban the adviser from being able to register. 
  • If an adviser keeps interacting after getting a notice to stop, a penalty may be issued. 

Useful guides on this topic

Mandatory tax adviser registration
From May 2026, all tax advisers who interact with HMRC on behalf of clients will be required to register with them. Who will be required to register? What conditions must be met? What are the consequences of non-compliance with 'mandatory tax adviser registration'?

Sole trader v. limited company: Tax differences & savings (2025/26)
Is it better from both a tax and legal point of view to run your business as a sole trader or as a company? Are there tax advantages in running a business as a company? What legal protections apply?

Which trading structure is best for me?
What are the key tax and legal differences between the different trading structures of the self-employed, a partnership or a company?

How to start a company
How do you go about creating a company? What do you need to do to start a company? A practical guide on how to form (incorporate) a private limited company covering the key points that you need to consider.

External links

HMRC: