Register for Making Tax Digital as an Agent [A Full Guide]

Making Tax Digital (MTD) is transforming how tax works in the UK – and for agents, it doesn’t change just what you submit, but how you manage your entire client workflow.

If you’re an accountant or bookkeeper, setting up correctly now is really important. From April 2026, MTD for Income Tax (MTD ITSA) applies to sole traders and landlords earning over £50,000, with thresholds expanding further in the following years.

This guide walks you through everything you need to know about how to register for MTD as an agent, with practical tips to make the process smoother.

Key points

• MTD isn’t a one-time registration, it’s a full system shift 🖥️
  Registering as an agent means setting up ongoing infrastructure, managing client authorisations, and handling continuous digital reporting. It moves your role from annual filing to a year-round workflow with HMRC and clients.
• The Agent Services Account (ASA) is your foundation 🖱️
  Everything in MTD runs through your ASA. It connects HMRC, your clients, and your software. If this isn’t set up correctly, you won’t be able to operate or submit on behalf of clients.
• Client authorisation and eligibility are common pain points 📋
  Existing authorisations don’t always carry over, and each client must approve you via a digital handshake. On top of that, enrolling clients too early or incorrectly can create reporting issues and extra admin.
• MTD introduces a significant operational workload, especially at scale 📑
  Each client must be signed up individually, and quarterly reporting quickly multiplies your workload. Small inefficiencies become major time drains when applied across dozens of clients.
• The right software determines whether MTD becomes manageable or overwhelming 💿
  While all tools meet compliance requirements, many still rely on manual bookkeeping, spreadsheets, and constant input. Solutions like ANNA remove that burden entirely by automating transaction tracking, categorisation, and submissions in the background.

What does ‘registering for MTD as an agent’ actually mean?

As an agent, you’re not just ‘signing up’ once. Instead, you need to:

• Set up your own MTD-ready infrastructure
• Get authorised by your clients
• Sign up each eligible client individually
• Use compatible software to manage submissions

MTD effectively shifts agents from annual filing to an ongoing, digital relationship with HMRC and clients.

You’ll need to register (or prepare to register) if you:

• Act for sole traders or landlords who meet MTD thresholds
• Submit VAT returns on behalf of clients
• Plan to handle quarterly updates and final declarations

The timeline works like this: from April 2026, sole traders or landlords earning over £50,000 will have to comply, then in April 2027 the threshold drops to £30,000, and finally in April 2028 to £20,000.

This means most agents with self-employed or landlord clients will have to eventually adapt.

How to register for MTD as an agent

Getting set up for MTD as an agent isn’t difficult, but it does require doing things in the right order. Miss a step, and you can run into issues later, from missing client authorisations to being unable to submit on their behalf.

Step 1 – Create an Agent Services Account (ASA)

Your Agent Services Account (ASA) is a dedicated HMRC account designed specifically for MTD. It sits alongside your existing agent account, not instead of it – and without it, you can’t operate under MTD.

The ASA acts as your central control panel for MTD. It allows you to:

• Access MTD services across VAT and Income Tax
• Manage and store client authorisations
• Connect your practice to MTD-compatible software

In other words, it’s the bridge between HMRC, your clients, and your software.

What you’ll need:

• Your existing HMRC agent credentials
• Your Government Gateway login details
• Your business information (such as Unique Taxpayer Reference number and postcode)

Once created, your ASA becomes the account you’ll use for all MTD-related activity going forward.

Step 2 – Check and migrate client authorisations

Although you may already be authorised to act for clients under Self Assessment, those authorisations don’t always transfer neatly to MTD.

Here’s what you need to do:

• Log in to your ASA
• Review which clients are already linked
• Identify any missing or incomplete authorisations
• Add or reconnect clients using your agent codes where needed

If a client isn’t correctly authorised in your ASA, you won’t be able to act for them under MTD, even if you’ve been handling their taxes for years.

Step 3 – Get MTD-compatible software

HMRC doesn’t provide software for MTD. That responsibility sits entirely with you.

To comply with MTD, you must use software that can:

• Keep digital records
• Submit quarterly updates directly to HMRC
• File end-of-period statements and final declarations

Keep in mind that your experience can vary significantly depending on the tools you choose.

Some software options still rely heavily on manual bookkeeping, spreadsheet uploads, and ongoing intervention and checks. Others take a more automated approach, handling categorisation, tracking, and submissions with minimal input.

Step 4 – Get client authorisation

Before you can act for a client under MTD, they must explicitly authorise you through HMRC.

This process is often called the digital handshake, and it replaces older authorisation methods for MTD services.

Here’s how it works:

• You create an authorisation request through your ASA
• HMRC generates a secure approval link
• You send the link to your client
• The client logs in and approves the request

Once completed, the authorisation is active, and you can act on their behalf within MTD.

Without this step, you won’t be able to:

• Submit updates
• Access client records
• Manage their MTD obligations

It’s a small step, but absolutely essential – and one you’ll need to repeat for each client.

Step 5 – Check if your client needs to sign up

Not every client needs to be enrolled immediately, so timing matters.

Before signing anyone up, you should confirm:

• They are registered for Self Assessment
• They receive income from self-employment or property
• Their qualifying income exceeds the relevant threshold

Signing up a client too early – or unnecessarily – can create avoidable complications, such as:

• Duplicate or conflicting records
• Incorrect reporting obligations
• Confusion around filing requirements

Step 6 – Sign up each client for MTD

Once everything is in place (ASA, software, and authorisation), you can officially sign up your client.

Here’s what happens during sign-up:

• You submit the client’s details to HMRC
• HMRC enrols them into the MTD system
• Their reporting shifts from annual Self Assessment to digital, periodic submissions

Each client must be signed up individually. There’s no bulk enrolment option, which means this step can take time if you manage a large portfolio.

Because of this, many agents choose to phase onboarding, prioritising clients who are closest to the threshold or most ready to transition.

Step 7 – Start using MTD

Once your client is registered, MTD becomes part of your workflow. From this point on, you’re not just filing annually. You’re managing an ongoing reporting cycle that includes quarterly updates, end-of-period statements, and final declarations. How involved you are will depend on your role.

You may act as:

• A main agent, responsible for the full submission process
• A supporting agent, handling specific tasks like bookkeeping or partial reporting

HMRC allows multiple agents to be linked to a client, but only one can be the main agent at any given time.

MTD also changes the nature of your role.

Instead of focusing purely on compliance, many agents are shifting towards a more advisory role. With more frequent reporting and up-to-date financial data, you’re no longer just recording what’s happened – you’re guiding clients.

That can include:

• Helping clients understand their real-time tax position
• Flagging cash flow issues sooner
• Offering proactive guidance on expenses, pricing, or profitability

In practice, this means less time spent chasing records and fixing errors at year-end, and more time spent delivering insights and value. For agents who embrace this shift, MTD isn’t just an administrative change; it’s an opportunity to build stronger, more strategic client relationships.

How to choose the right MTD software as an agent

Choosing MTD-compatible software is one of the biggest decisions that will shape how much work MTD creates for your practice.

On paper, all compliant tools can submit data to HMRC, but in reality, they differ significantly in the amount of manual effort required behind the scenes.

Here’s how to find the best fit for you:

1. Start with your workflow, not the features

It’s easy to get distracted by feature lists, but the real question is: how much work does the software create for you and your clients?

Some tools still rely on:

• Manual transaction categorisation
• Regular spreadsheet uploads
• Ongoing client input and corrections

Others are designed to minimise that effort through automation.

The difference becomes much more noticeable under MTD, so make sure your pick fits your workflow well.

2. Consider your client base

There’s no one-size-fits-all solution, so it’s worth segmenting your clients like this:

• Spreadsheet-driven clients may be comfortable with simple bridging tools, but will still require manual upkeep.
• Low-engagement clients benefit from automation, as they’re less likely to keep records up to date.
• Growing businesses may need more detailed reporting and flexibility, often found in full accounting platforms.

Choosing the wrong setup can lead to more chasing, more corrections, and more pressure every quarter.

3. Think about scalability

If you manage dozens (or hundreds) of clients, even small inefficiencies quickly add up. A process that takes an extra 10 minutes per client, per quarter, becomes a significant time cost across your portfolio.

Why automation matters more under MTD

Under the old Self Assessment system, inefficiencies could be absorbed into a once-a-year push. MTD removes that buffer.

With quarterly deadlines, manual processes quickly become repetitive. However, when transactions are tracked automatically and categorised in real time, there’s less to fix later and far less need for back-and-forth with clients.

For agents, this isn’t just about saving time. It’s about making MTD sustainable at scale.

How ANNA removes admin from your MTD workload – for FREE

Most MTD software helps you stay compliant. But as an accountant or bookkeeper, the real challenge is capacity.

The more clients you manage, the more admin pressure builds, not just for managing your clients, but also for keeping track of your own business finances.

ANNA is designed differently. Instead of giving you more tools to manage, it removes much of the work altogether. It handles MTD compliance in the background so you can focus on supporting your clients.

Here’s what ANNA can do for your practice:

• Prepare and file 2025/26 Self Assessment for free: No additional cost, no extra software, just connect to HMRC.
• Get MTD updates prepared automatically: Quarterly submissions are ready in the background, without manual prep or last-minute work.
• Handle bookkeeping with Auto Accountant: Transactions are recorded and categorised in real time, so you’re not fixing books every quarter.
• Calculate and file VAT automatically: Compliance is seamless without running separate VAT workflows.
• Create and send invoices with built-in payments: You can invoice, get paid, and stay organised in one place.
• Stay on track with a personalised tax calendar: Deadlines are tracked automatically, reducing the need to chase clients.
• Run simple payroll for one employee: PAYE and NICs are calculated and submitted without extra admin.
• 24/7 human support: Professional support is always available for your tax questions.

There’s no setup, no learning curve, and no need to maintain spreadsheets or use multiple tools. For your practice, that means fewer errors, less back-and-forth, and more time to focus on higher-value work.

Try ANNA today and get MTD sorted in no time, for free.