TaxCalc Blog

What is an ACSP and why does it matter?

From 18th March 2025, any third party filing with Companies House on behalf of clients has been able to register as an ACSP. That includes accountants, solicitors, company formation agents and chartered secretaries.

There are three key reasons why you may wish to consider registration:

1. From Autumn 2025 (exact date yet to be announced), any director or person with significant control (PSC) will need to have their identity verified to allow submission of their confirmation statement. ACSPs are permitted to verify the identity of their clients. and inform Companies House of such, otherwise the individuals will have to do so themselves either using an online GOV.UK service or in person at the post office.
2. Also from Autumn 2025, any newly appointed director or PSC will need to be verified before that appointment form can be filed with Companies House. Again, if you do not do this as an ACSP the individual or individuals will have to do this themselves and provide you with their ‘personal code’.
3. It will be mandatory from Spring 2026 (again, exact date unknown) for any 3rd party to file documents with Companies House unless they are registered as an ACSP.

In simple terms, if your firm helps clients set up companies or file documents, you will need to be registered as an ACSP to keep doing that from Spring 2026 and you may wish to consider early registration to do the identity verification process yourself.

How to register as an ACSP?

Registration is via GOV.UK  and you must meet their qualifying criteria.

• You can register as a company, partnership or sole trader
• You will need to verify your own identity (employees will not need to)
• Your firm must be registered with a UK anti-money laundering (AML) supervisory body.
• You must pay the £55 registration fee.

Once your registration has been approved you will receive a unique ACSP ID and online Companies House account that is separate to your existing Companies House WebFiling account.

ID Verification: The new front line in compliance

From autumn 2025, identity checks will be mandatory for:

• New and existing directors
• Persons with Significant Control (PSCs)
• And, from Spring 2026, anyone filing on a company’s behalf

An individual can be verified, either:

1. Using an ACSP (like your firm) – Perhaps the most reliable and client-friendly option
2. In-person at the Post Office – If this method is chosen, Directors and PSCs must do so themselves
3. Using a GOV.UK One Login</span style="font-weight:600;"> – If this method is chosen, Directors and PSCs must do so themselves

But here’s the catch - to verify clients, your systems must match government-level standards. That means investing in the technology or the training that can satisfy those standards.

You have two choices for verifying an individual’s identity as an ACSP:

1. Use biometric identity verification (IDV) technology capable of validating the cryptographic features of the document.
2. Enrol your team on a Home Office Security style training course to be able to spot potential identity fraud and document tampering. This will allow you to continue to conduct the manual ID checks that you may be doing today.

It will be for you to determine the costs and risks associated with both options and indeed whether you will offer the service to your clients at all or, alternatively, ensure that they complete the verification process themselves.

Opportunities for accountants

1. Own the client relationship – Offer a full suite of services, from filings to ID verification
2. Generate new revenue – Charge for verification and compliance checks
3. Stand out from competitors – Become a trusted expert in the new regime

Of course, with power comes great responsibility. As an ACSP, you’ll need to:

• Report any changes to your firm within 14 days
• Maintain ID verification records for at least 7 years
• Be ready for Companies House spot checks
• Always be registered with an AML supervisory body, including HMRC.

Impact on client workflows: what you need to prepare

Onboarding just got more complex.

For existing clients:
They’ll need to verify their identity before you can file for them. Some may be confused or reluctant. Your guidance will make the difference.

For new clients:
ID verification becomes step one. That means your onboarding process needs to be airtight and, ideally, integrated with your practice management tools.

Want a competitive edge? Do it all in-house. That’s where ACSP status pays off.

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