Can You Do Your Self Assessment Without an Accountant?
- 6 min read
Nothing in the rules says you need an accountant to file a Self Assessment return. HMRC provides the online service and expects people to use it themselves. The real question is whether your affairs are simple enough that you would be comfortable signing off the figures.
What the process involves
If you have not filed before, you first register with HMRC for Self Assessment. You then complete the return after the tax year ends on 5 April, using the online service or, if you prefer, the paper SA100 form. HMRC works out what you owe from the figures you report.
The return itself is a form. The work is upstream of it: knowing your income and allowable expenses for the year, with records to back them up.
- Register in time. If you need to file for the year just ended and have not filed before, you must tell HMRC by 5 October, and you could be fined if you do not
- File by the deadline for your method. Paper returns have an earlier deadline than online ones, so check the dates for the current year on GOV.UK
- Pay any balance by 31 January, and know whether payments on account apply to you
- Keep your records, such as bank statements and receipts, so you can support what you reported
Where people get caught
Registering late is the one that surprises new sole traders, because nothing prompts you. The 5 October registration date falls well before the filing deadline.
The second is paying. Filing on time does not mean you have paid on time, and the January bill can include payments on account for the following year as well as the balance for the one you just filed.
The third is records. A return built from memory in January is where allowable expenses go missing and personal spending sneaks in.
Filing and paying are separate deadlines with separate consequences. If you cannot pay, file anyway and contact HMRC about a payment arrangement.
When it is reasonable to go it alone
A return is usually straightforward when your income comes from one source, your expenses are ordinary, and you have kept clean records through the year.
It is worth paying for advice when something about your position is genuinely uncertain: a mix of employment and self-employment with complicated reliefs, property sales, foreign income, or a tax year in which you moved in or out of the UK. The cost of getting one of those wrong is usually larger than the fee.
What helps either way
The best preparation for filing yourself, or for handing it to someone else, is the same: record income and expenses as they happen, keep the supporting documents, and keep your bank transactions reconciled to your records.
Taxmo prepares your Self Assessment figures from the records you keep and shows you the return, so January is a review rather than a reconstruction. Direct Self Assessment submission to HMRC is not available yet, so the filing step itself is done on the HMRC service. VAT is different: Taxmo submits VAT returns to HMRC directly over Making Tax Digital.