{"id":38067,"date":"2026-05-19T11:23:48","date_gmt":"2026-05-19T10:23:48","guid":{"rendered":"https:\/\/figsflow.com\/uk\/?p=38067"},"modified":"2026-05-19T11:24:08","modified_gmt":"2026-05-19T10:24:08","slug":"tax-adviser-registration-with-hmrc","status":"publish","type":"post","link":"https:\/\/figsflow.com\/uk\/tax-adviser-registration-with-hmrc\/","title":{"rendered":"Tax Adviser Registration with HMRC: What Has Changed & What You Need to Do"},"content":{"rendered":"\t\t
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If you are paid to deal with HMRC on behalf of clients, whether as an accountant, bookkeeper, tax agent, or in any other capacity, the way you register has changed. From May 2026,\u00a0tax adviser\u00a0registration\u00a0with HMRC is a legal requirement, backed by sanctions\u00a0for\u00a0those who do not comply.<\/span>\u00a0<\/span><\/p>

This article explains what the old system looked like, what replaced it, who needs to act and when, and what you\u00a0actually need\u00a0to do.<\/span>\u00a0<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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The Old System Was Fragmented<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
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For years, HMRC agent registration was not a single process. It was a collection of separate routes, each tied to a specific tax service. Self Assessment required a written application for an SA agent code, which could take up to 40 working days. Corporation Tax needed a separate code through the same slow process. PAYE, VAT, CIS, and other services each had their own paths, their own timelines, and in many cases their own paper forms.<\/span>\u00a0<\/span><\/p>

There was no single account, no unified view, and no legal obligation to register at all.<\/span>\u00a0<\/span><\/p>

Firms could interact with HMRC on behalf of clients with minimal checks. Standards were inconsistent, HMRC had no reliable way to verify who was operating, and there was little to stop unscrupulous actors from working largely unchallenged.<\/span>\u00a0<\/span><\/p>

The Agent Services Account, introduced for <\/span>Making Tax Digital<\/span><\/a>, was a step forward. But it sat alongside the old codes rather than replacing them. Many firms ended up running both: old agent codes for legacy services and a separate ASA for MTD. Two systems, neither complete.<\/span>\u00a0<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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What Is MMTAR? <\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
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MMTAR stands for Modernising and Mandating\u00a0Tax Adviser\u00a0Registration. It is the government’s programme to replace the patchwork of existing registration routes with a single, legally required process.<\/span>\u00a0<\/span><\/p>

Announced at Budget 2025 following a public consultation in October 2024, MMTAR introduces a legal obligation for anyone who is paid to interact with HMRC on behalf of clients to register with HMRC. The mechanism for that mandatory\u00a0tax adviser\u00a0registration\u00a0is the\u00a0<\/span>Agent Services Account<\/span><\/a>. The ASA, which previously existed as one of several options, is now the universal gateway for all tax agents and advisers.<\/span>\u00a0<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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Who Is a Tax Adviser Under the New Rules? <\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
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HMRC’s definition is deliberately broad, and it catches many more firms than the phrase “tax adviser” might suggest.<\/span>\u00a0<\/span><\/p>

Under MMTAR, you are a\u00a0tax adviser\u00a0if you are paid to interact with HMRC on behalf of clients. That includes providing advice on tax, acting as an agent, helping prepare documents that HMRC will rely on to\u00a0determine\u00a0a client’s tax position, filing returns, sending claims, and contacting HMRC by phone, post, email, app, or online portal.<\/span>\u00a0<\/span><\/p>

You are required to register\u00a0with HMRC as a\u00a0tax adviser\u00a0even if you do not describe yourself as a\u00a0tax adviser, even if tax work is incidental to your main services, even if you only act for a single client, and even if your business is based outside the UK. Sole traders must register in their own name. Interactions made through third-party software or API connections count.<\/span>\u00a0<\/span><\/p>

Registration is\u00a0required\u00a0at firm level. Individual employees do not register separately, though HMRC will carry out checks on certain people within the business, referred to as relevant individuals.<\/span>\u00a0<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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Who Does Not Need to Register? <\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
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The exemptions are narrow. You\u00a0are not required to\u00a0register for an agent services account if you fall into one of the following categories:<\/span>\u00a0<\/span><\/p>