Readers’ forum: Digital signature

Writing for Taxation magazine, BKL tax partner David Whiscombe comments on whether a self-assessment tax return declaration can be signed online.

As part of my firm’s embracing of the digital age we are about to introduce something called a ‘client portal’. I am given to understand that this will allow clients to sign in to our systems and electronically sign documents. One such document will be the annual self-assessment tax return.

I have been asked what we are legally required to hold in terms of signed documents. Do we still need a ‘wet’ signature on the tax return declaration or has that become obsolete?

I look forward to replies.

Query 18,767– Autograph.


Reply by ‘Beaky Al’

I do not believe that an authorised agent is or ever has been required by law or HMRC practice to hold the client’s ‘wet’ signature on the tax return declaration before filing the tax return online.

By appointing a person as his tax agent, the client is authorising them (subject to the agent’s terms of business) to file tax returns on their behalf. And by notifying HMRC that he has appointed someone as his tax agent, the client is authorising HMRC to accept returns made on his behalf by that person.

The processes and procedures by which a tax agent obtains confirmation from a client that they are instructed to file a particular set of figures is something that concerns the client and the agent only. In practice, the reason why some tax agents still require a wet signature on a hard copy of a return is to establish beyond any possible doubt the figures that the client has approved. This should avoid any subsequent arguments about ‘who said what to whom’ if it turns out that the return was incorrect.

A similar degree of protection can be afforded by, for example, emailing the client a pdf of the draft return and having the client confirm by email that the return is approved. However, in theory, this is not quite as secure evidentially as a wet signature unless special measures are taken: emails can be intercepted and changed and pdfs can be altered. A ‘client portal’ designed to give an auditable trail of what exactly the client approved should be just as satisfactory as a wet signature on a hard copy.

The article is also available on the Taxation website.



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