64-8 Setup, Usage and Guidance

Article ID: 2678
Last updated: 29 Mar, 2022

The below information will go through the process of applying for authorisation to act on behalf of your clients. The heading below will allow you to skip to the relevant section (if applicable):

Completing the 64-8 form.

What happens after successful activation of the 64-8?

Potential issues or errors when submitting the 64-8

‘Data does not match’ 7001/ 7008 error

Completing the 64-8 form

Step 1: Ensuring your required agent details are entered into TaxCalc

  1. Ensure you have entered your HMRC Filing Credentials and email address. Please consult the How do I enter online filing credentials (Practice users)? Knowledge Base article for instructions on how to enter your HMRC Filing Credentials.
  2. You must also enter your Agent Reference Number for each client for whom you wish to perform the 64-8 service. Please consult the How do I register as an agent with HMRC? Knowledge Base article for instructions on how to acquire your Agent Reference Number.

Step 2: The capabilities of TaxCalc's 64-8 software

  1. Print a 64-8 form to be signed by your client and posted to HMRC.
  2. Note that File by Internet (FBI) for 64-8s is only available for Individuals or Limited Companies. FBI does not cover Partnerships, Trusts, Tax Credits, PAYE or VAT – these will require printing the 64-8 and obtaining the client’s signature before posting to HMRC.

Step 3: Client details

  1. Ensure you have entered the following required information into ‘Client details’ in Practice Manager. Note that data marked * (and the Client’s Code from their record in Practice Manager) is the only data sent via FBI.
  • Individuals
    • Unique Taxpayer Reference (UTR)* & National Insurance Number (NINO)*
    • Name & address/postcode*
  • Companies
    • UTR* & Company Registration Number (CRN)*
    • Company name & registered office address/postcode*
    • Associated directors, secretaries, etc via ‘Relationships’
  • Partnerships
    • UTR
    • Partnership name & address/postcode
    • Associated partners, etc via ‘Relationships’
  • Trusts
    • UTR
    • Settlor/Trustee name & address/postcode
    • Associated trustees etc via ‘Relationships’
  • Tax Credits
    • As individuals above, plus joint claimant’s NINO if required
  • PAYE
    • In addition to above, the PAYE reference & PAYE Office Code (employers only)
  • VAT
    • In addition to above, the VAT registration number

Step 4. Creating the 64-8

  1. In Practice Manager, right-click on the client and choose Open in HMRC Forms.
  2. Click New Form followed by Create.
  3. Open the 64-8 by double-clicking on it.

Step 5. All Client Types

  1. Using the left-hand menu, go to Page 1.
  2. The left-hand side of Page 1 (Authorising your agent) will be populated with details from Practice Manager. Note that you may wish to remove the client’s telephone number if posting to HMRC.

Step 5A. Individuals

  1. You now need to review the right-hand columns and enter any additional information.
  2. Note that to FBI the 64-8, the ‘Individual/Partnership/Trust Tax Affairs’ section must be the only section with data entered. If you need to use any other sections then you must print the 64-8 and obtain the client’s signature before posting to HMRC.

Step 5B. Companies

  1. Use the Select Director button on the left to choose the signatory name.
  2. You now need to review the right-hand columns and enter any additional information.
  3. Note that to FBI the 64-8, the ‘Corporation Tax’ section must be the only section with data entered. If you need to use any other sections then you must print the 64-8 and obtain the client’s signature before posting to HMRC.

Step 5C. Partnerships and Trusts

  1. Use the Select Partner or Select Settlor/Trustee button on the left to choose the signatory name.
  2. You now need to review the right-hand columns and enter any additional information.
  3. You must print the 64-8 and obtain the client’s signature before posting to HMRC.

Step 6. Printing the 64-8 for client’s signature

  1. Using the left-hand menu, go to Check and Finish > Print.
  2. You will be asked if you would like to ‘Update this client’s 64-8 status?’. Your answer will then be recorded in the Engagement tab of their client record.
  3. The form, once signed by the client, will then need to be posted to the address recorded in Page 2, Section 5 of the 64-8.           

Step 7. Filing the 64-8 online (Individuals & Limited Companies only)

The 64-8 online filing process consists of three stages that ensure that the client has agreed to your request to act on their behalf:

  1. Submit the 64-8 via FBI to HMRC.
  2. HMRC will then process the 64-8 request and post an ‘activation code’ to the client.
  3. You then ‘activate’ the 64-8 (via FBI) once the client has advised you of the activation code.
  4. Ensure you have completed the 64-8 as required in the steps above. Then using the left-hand menu, go to Check and Finish and select File Online.

Step 7A. 'Submit' the 64-8 via FBI to HMRC

  1. The 64-8 Online Submission screen summarises the data to be sent via FBI.
  2. Click Send to start the submission process.
  3. After closing the submission window, you will be prompted to update Practice Manager (where the client’s 64-8 status will be updated within the Engagement screen).
  4. A confirmation will be shown in green on the main screen.

Step 7B. HMRC process the 64-8 request and post an ‘activation code’ to the client.

Step 7C. 'Activate' the 64-8 via FBI.

  1. Receive the activation code from your client (sent to them by HMRC).
  2. In Practice Manager, right-click on the client and choose Open in HMRC Forms.
  3. Open the 64-8 by double-clicking on it.
  4. Using the left-hand menu, go to Check and Finish > File Online. You will see the original Submit successful message.
  5. Click on Activate and enter the authorisation code in the top box. Ensure you enter the code in upper case, including the SA or CT. Do not delete the Authorisation request ID in the second box.
  6. Click Send to start the activation process.
  7. After closing the submission window, you will be prompted to update Practice Manager (where the client’s 64-8 status will be updated within the Engagement screen).
  8. A confirmation will be shown in green on the main screen.

What happens after successful activation of the 64-8?

  • It can take up to 24 hours for a 64-8 related to an Individual to appear on your HMRC client list.
  • It can take up to 72 hours for a 64-8 related to a Limited Company to appear on your HMRC client list.
  • Note that you can still file the client’s SA100 or CT600 tax returns at any time.

Potential issues or errors when submitting the 64-8

There are two common problems which can occur when submitting the 64-8 (Step 7A): The ‘1046 error’ and the ‘Data does not match error’.

1046 error

A 1046 error can be caused by one of two situations: An Incorrect User ID / Password / Agent Reference Number or a Problem with the UTR.

Incorrect User ID / Password / Agent Reference Number

When submitting the 64-8, 1046 errors can be generated when any of the following are incorrect:

  • Your HMRC User ID
  • Password
  • Agent Reference Number

Step 1 should help you fix this type of 1046 error, as checking and correcting these details will remove the problem.

Problem with the UTR

The other situation is when the supplied UTR may not be for the service you are trying to activate. This happens when you are submitting a 64-8 for the Company but the client has given you their own personal Self Assessment UTR in error (or vice versa).

  1. In this situation, it is best to check any HMRC documents that the client has for the correct UTR.
  2. Update Practice Manager with the correct UTR.
  3. Follow the above process from Step 4 (however, make sure to make a new 64-8 and delete the first version).

Alternatively, the problem with the UTR may be because of one of these two specific reasons:

  • Limited Companies Only: If the company is recorded as being struck off/dissolved with Companies House, the UTR may be flagged as ‘inactive’ as part of this process. This will then generate a 1046 error when attempting to file a 64-8 for that company.
  • Individuals Only: If the individual is or was a civil servant or government employee, the UTR may be flagged as ‘inactive’ and a paper 64-8 may be required. You will then need to create a new 64-8 to send to PD1 (Public Department 1 of HMRC).

‘Data does not match’ 7001 / 7008 error

This is caused by the details provided by the client not matching HMRC’s records. This error is usually caused by the Individual/Company Postcode provided by your client not matching the one held by HMRC. This can often occur when the client has moved in recent years.

The client themselves will have to contact HMRC to update their records.

An incorrect National Insurance Number can also generate this error. It is best to check any HMRC documents that the client has for the correct NINO.

  • Note that you can still file the client’s SA100 or CT600 tax returns at any time.
Article ID: 2678
Last updated: 29 Mar, 2022
Revision: 15
Views: 9887
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