How agents register clients

Agents must sign clients up one by one through the Agent Services Account (ASA). HMRC does not offer bulk enrolment for Making Tax Digital for Income Tax — each mandated client needs an individual sign-up with accurate business start dates and income sources.

Before you start

Confirm the client is mandated (or will be from their next start date), that you hold a valid authorisation on your ASA, and that they have chosen compatible software. The agent sign-up journey is separate from the taxpayer-facing GOV.UK link — using the wrong route causes rejections and duplicate records.

• Use the agent-specific MTD ITSA sign-up service inside your ASA, not the public taxpayer URL.
• Collect the client's UTR, National Insurance number, and each trade or property business name.
• Record accurate start dates for every income source — if a business began more than two tax years ago, HMRC allows defaulting to 6 April 2023 in many cases.
• The flow checks whether the client already has software connected; resolve that before completing enrolment.

After sign-up, link your practice software and verify quarterly obligations appear. See Adding client authorisations and Client sign-up process for the full agent workflow.