From your books to your CT600: a year-end walkthrough

The records you keep during the year should make your tax return easier to prepare. In filefast, the link is “Fill from Books”: once your bookkeeping year is closed, you can bring its figures into the declaration and review them there.

This guide describes the workflow. It is not a report of a customer filing.

1. Review the records behind the totals

Start with the bank, transaction categories, customer invoices and supplier bills. Check that payments are linked to the right documents and that unfinished entries have been dealt with.

A bank balance alone does not explain the year’s profit. An unpaid customer invoice or supplier bill can also matter, so include those records in your review.

2. Work through Year end

Open the year you are preparing to close. The Year end page groups the remaining work into checks, with links back to the relevant records.

It asks two practical questions about the boundary between years: did you pay for something you will use next year, and did the company incur a cost that has not yet been billed?

It also brings equipment and other year-end items into the review. Where a decision needs your attention, follow the explanation and resolve it before continuing.

Blocking items keep “Close year” unavailable until they are addressed. Warnings are identified separately so you can read them before deciding how to proceed.

3. Close the reviewed year

When the year is ready, confirm “Close year”. Transactions in that year are then protected from ordinary editing.

If you discover something that needs changing, use the explicit reopening process and review the affected figures again. Closing the bookkeeping year is a preparation step; it does not submit a tax return.

4. Bring the figures into the declaration

On the declaration’s Inputs step, choose “Fill from Books”. This brings the closed year’s figures into your return preparation and identifies their source.

Review the transferred amounts, complete the remaining questions and continue to the Corporation Tax calculation. Open its explanations where you want to understand how a figure contributes to the result.

5. Review before sending

Inspect the prepared filing documents and checks before confirming the declaration. Submission remains a deliberate step after that review.

This is the benefit of keeping the two jobs connected: everyday records support your year-end figures, and those figures become the starting point for a return you can inspect before sending.

Explore bookkeeping in filefast.

Matvei Kostiuchenko, Founder of filefast. Not an accountant. General information, not a substitute for regulated tax advice.