Self Assessment software prepares your return from records kept through the year rather than from a reconstruction in January. Income and expenses are already categorised, evidence is already attached, and what is left is checking the figures and declaring them.
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The return itself is not difficult. What is difficult is reconstructing twelve months of trading from a bank statement, a carrier bag and memory, in the week before a deadline, having not looked at any of it since the last time.
Nothing about the form causes that. Records kept as the year goes turn the return into an hour of checking, which is why the fix is bookkeeping rather than better tax software.
| Date | What is due |
|---|---|
| 5 October | Register for Self Assessment if you started trading in the tax year just ended |
| 31 October | Paper return deadline |
| 30 December | File online if you want tax collected through your PAYE code |
| 31 January | Online return, balancing payment, and first payment on account |
| 31 July | Second payment on account |
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COMMON QUESTIONS
It prepares the figures and keeps the records that support them. Filing and the final declaration remain yours, which is how it should be — you are the one signing it.
They are visible as they accrue rather than arriving as a January surprise. This is the single most common cash shock in a second year of trading.
Yes, and it belongs on the same return. Self Assessment looks at your whole position, so employment, self-employment and property income are considered together.
It estimates the liability as the year goes, from what has been recorded so far, so January is not the first time you see the figure. Treat it as an estimate and confirm with your accountant — it cannot know about reliefs you have not told it about.
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