Property developer with an 18-month year end: splitting profit between two CT600s
Short version. A property developer with an 18-month accounts period usually needs two CT600s. HMRC identifies property development as an example where a transactions basis may be more accurate than sharing profit by days.
On this page
1. Understand the uneven-profit example
HMRC CTM01405 describes trades with uneven profit and a few identifiable transactions. Its property-development example illustrates why a transaction basis may better reflect the periods than a simple daily share. It does not authorise arbitrary movement of profit between returns.
Fictional Birch Development Ltd prepares accounts from 1 April 2024 to 30 September 2025. A completed development contributes £90,000 profit in the first return and the later period incurs £10,000 expenses. A time share of the net £80,000 would obscure that pattern. Where the prepared transactions basis is appropriate, enter the first period’s income and costs in CT600 1 and the later period’s income and costs in CT600 2.
Decide whether the company is trading in property or carrying on an investment property business. The product’s property rental fields represent rent and rental expenses. Development sales belong in the appropriate trading figures, rather than being labelled rent simply because land is involved.
2. Check losses and adjustments
Enter company-level opening loss pools on CT600 1 only. The engine carries the unused pools from CT600 1 into CT600 2. Return 2 claim controls use that remainder. A blank optional claim uses the existing default. An explicit £0 claim claims nothing.
Review each return’s computation and final unused pools. A loss arising in the final return does not automatically amend an earlier CT600 or claim a carry-back repayment. Follow the existing loss guidance for that choice.
Keep the full statutory accounts P&L on its own tab. See time apportionment or actual figures and the entry steps.