Next Making Tax Digital quarterly update deadline: 7 November 2026.Start filing now

Summary

How to add one client, choose how they will file, and complete the HMRC identity check

For Accountants

Adding a Client

What this is

Add Client creates one client in your practice and asks HMRC, before anything is saved, whether the person exists and whether you already act for them. If HMRC knows the relationship the client arrives authorised; otherwise the client page opens ready to send an invitation. To add many clients at once, use Import clients.

What you see on screen

Add Client at /app/clients/add is a single form, Client Details:

  • Authorisation type - Main agent or Supporting agent
  • How will this client file? - Fully managed, Review or Self-filing
  • How will this client’s figures arrive? - Transactions or Summary spreadsheet, required. Choosing Transactions shows a How records can get in panel listing the ways records can reach you
  • Client Name - required
  • Client Email - required; the invitation is sent to it
  • Phone - optional
  • National Insurance Number - required, in the format AB123456C
  • Postcode - required, and checked against HMRC’s records for that National Insurance number
  • Notes - optional, for your own reference
  • Add Client

The page header explains that once your client has authorised you and HMRC returns their businesses, you open the client to set up how their records reach you.

The form is greyed out with a Connect to HMRC first notice until your practice is connected, and asks you to set your Agent Reference Number in Settings if none is saved or HMRC has rejected the one that is.

Add client form

How to add a client

  1. On Clients or Work, click Add client. The form’s back control returns to the page you opened it from.
  2. Choose Main agent or Supporting agent.
  3. Choose how the client will file:
    • Fully managed - your practice requests the records, prepares the update and files it.
    • Review - the client sends their spreadsheet, then your practice checks and files it.
    • Self-filing - the client files their own updates; your practice watches HMRC’s status and can send reminders.
  4. Under How will this client’s figures arrive?, choose Transactions if the client’s income and expenses will be recorded one by one, or Summary spreadsheet if they will send category totals each quarter. Until you choose, the answer your practice uses most often is selected (a summary spreadsheet when you have no clients yet, or when the two are tied).
  5. Enter the client’s name, email address, National Insurance number and the postcode HMRC holds for them.
  6. Click Add Client.
  7. aligned.tax checks the identity with HMRC. If it passes, the client’s page opens and an HMRC invitation is created for you to send. See Authorising a Client with HMRC.

When you request a quarterly spreadsheet, choose category totals or individual transactions for that request. The client chooses the source for each update when they file.

With Transactions, the How records can get in panel lists the routes your practice can use: you add records in aligned.tax (type in, or upload a photo or PDF), or you import a spreadsheet or CSV of the client’s transactions. When your practice can use email records, it also lists the client emailing receipts to their own aligned.tax address, and says you will be helped to send them an email setup link once they have authorised you.

Things to know

  • The identity check happens before the client is saved. If HMRC cannot match the National Insurance number and postcode, nothing is created and the form tells you which detail to check. This is deliberate: a client that cannot be authorised is not worth having in the list.
  • The postcode must be the one HMRC has, which may be an old address if the client has moved without telling HMRC.
  • Invalid prefixes. National Insurance numbers starting BG, GB, NK, KN, TN, NT or ZZ are rejected.
  • One client per National Insurance number in your practice. A duplicate is refused with “A client with this NINO already exists”.
  • HMRC may already know you act for the client. Then the client arrives as authorised and no invitation is created.
  • No UTR is asked for. HMRC identifies the client by National Insurance number for Making Tax Digital for Income Tax.
  • Fully managed is selected by default. You can change the filing arrangement later from the client details tab.
  • The records method can be changed later on the client’s page, which also has a Get this client’s records in section once the client is authorised and HMRC has returned their businesses, where your practice can use email records. See The Client Page.
  • Self-filing clients do not create filing work for your practice. They appear under Self-filing on Work, so you can monitor HMRC’s status and send a reminder.

If something goes wrong

What you see Why What to do
Connect to HMRC first The practice is not connected Use the Connect to HMRC link on the form
A notice about your Agent Reference Number No ARN is saved, or HMRC rejected the saved one Set or correct it in Settings, then try again
The identity check could not be completed HMRC did not answer Wait a minute and click Add Client again
HMRC did not recognise the details National Insurance number or postcode does not match HMRC’s record Confirm both with the client; the postcode must be the one HMRC holds
“A client with this NINO already exists” The client is already in your practice Look them up on Clients

FAQ

Can I change the details later?

Yes, with Edit in Client details on the client’s page. Changing the National Insurance number or postcode triggers a fresh HMRC check and may need a new invitation.

What is the difference between Main agent and Supporting agent?

It is the HMRC relationship type you are asking the client to authorise. A main agent has the fuller set of permissions with HMRC. If unsure, choose Main agent.

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