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Dealing with the Revenue Service on behalf of someone else

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There are some circumstances where you may want someone else to deal with your tax and social security affairs on your behalf. This can be done by completing a form of authority.

Forms of Authority
Both the Income Tax (Guernsey) Law 1975 and the Social Insurance (Guernsey) Law 1978 contain confidentiality provisions that mean anyone who works for the Revenue Service is unable to discuss an individual's tax or contribution affairs, with a third party, without the individual's consent (although the Laws do contain some legal gateways for sharing certain information).

If someone discloses information to a third party, without the appropriate legal gateway or consent, they can be fined, imprisoned or both.

It is recognised that individuals may want someone to help them with their income tax or contribution affairs, whether this is a professional advisor such as an accountant who may produce accounts for the individual's business, for example, or a trusted friend or relative. 

The Revenue Service has two different forms of authority that can be completed, one for where professional advisors are appointed and one for all other individuals. You can cancel an authority at any time by completing a withdrawal form. All of these are in the downloads section of this page.

  • Why are they needed?

    • It may be that you don't understand tax and you want someone to help you complete your return, and deal with any enquires that are raised. It could be that you need someone to help you with a question regarding your social security contributions. 
  • What do they do?

    • The completed form of authority gives us your permission to discuss your tax and contribution affairs, or the affairs of your company, with the third party of your choosing. 
  • How do they work?

    • The authority would be noted on the systems that we use, so there is a record of the authority in place. When that person phones we will then know that they have permission to discuss your affairs and we can talk openly with them, answering any questions they may have.

      If the third party is a professional advisor, such as an accountant, any letters or queries would be directed to the accountant instead of you, and the accountant would get a copy of any assessments issued. The actual assessment would still be sent to you, so you will still know what you need to pay. 

      If the authority is not for a professional advisor, you have the option on the form of authority to request that the third party be sent all correspondence issued, on your behalf, in which case all assessments, reminders, letters etc would be sent in your name, but to the third party and not to you.

      A form of authority allows the third party to submit your tax returns on your behalf, although it is still your responsibility to ensure that the form is correct and submitted by the due date. If your tax return is submitted late, you will still be liable to pay any late filing penalties imposed.
  • Who can be given authority to deal with the Revenue Service?

    • Using a form of authority you can appoint anyone to deal with the Revenue Service on your behalf, whether that be a relative (your mother, spouse, son etc.) or a professional person such as an accountant.
  • Are there any circumstances where you don't need a form of authority?

    • If there is a power of attorney or guardianship order in place then the Revenue Service can discuss the affairs of the customer with that person or guardian, without a form of authority. We would need to see the relevant court document as evidence of the power of attorney or guardianship order. In the case of a guardianship order then it has been determined that the individual customer is not capable of dealing with their own affairs, and as such they would be unable to sign the authority.
  • How long does a form of authority last?

    • The form of authority, once signed, remains in place until it is withdrawn by you and the Revenue Service is told that the person to whom authority has been given is no longer acting on your behalf. This can be done by completing the withdrawal form. Following the introduction of independent taxation in 2023 a form of authority which covered two parties who were jointly assessed will only cover the lead tax payer. The remaining party will need to submit a new form of authority in their name.
  • What happens to an authority when someone dies?

    • The authority would end on death. It would then be for the personal representative of the estate to deal with the tax and contribution affairs of the customer to the date of death, and with their estate. They need to submit a further form of authority if they wish to appoint someone to deal with the estate on their behalf.
  • Do you accept a verbal authority?

    • We may accept a verbal authority from you, during a telephone call, to discuss your affairs with an alternative caller, at that time. However, that authority would only last for the duration of that telephone call. If you wish for that person to deal with your ongoing affairs, then we must have the authority in writing. 
  • How is an authority cancelled?

    • The authority can be cancelled verbally or in writing, but we would prefer that you complete the withdrawal form, as this means we will have all the information we need. 




    Form of Authority (individual customers) Form of authority (professional advisors) Withdrawal of Form of Authority

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