Residential Property Developer Tax (RPDT) is a 4% tax on the profits a company makes from developing UK residential property, above an allowance of £25 million a year shared across its group. It is reported on CT600N, the RPDT supplementary page of the Company Tax Return, and paid with Corporation Tax. Only the largest developers pay it, but members of a developer group may still need the page. This guide explains when you need a CT600N, how to complete it in Tax Optimiser, and what every box from N1 to N285 means.
When a company needs a CT600N
File a CT600N, and tick box 144 on the CT600, if in the return period the company:
- records RPDT in box 497 of the CT600, or has RPD profits to report even where the allowance covers them (Section 4);
- is the group’s nominated allocating member and is sharing out the group’s allowance (Section 1);
- is a joint venture company whose allowance is restricted because of an excluded member (Section 2); or
- claims or surrenders RPDT group relief, including for carried-forward losses (Section 3).
RPDT applies to accounting periods ending on or after 1 April 2022. A period that straddles that date is split, and only the part from 1 April 2022 is charged.
How the tax works
RPDT is charged at 4% on RPD profits above the allowance. RPD profits are the company’s trading profits from residential property development, adjusted under the RPDT rules, plus its share of the profits of joint ventures, less RPDT losses and RPDT group relief. They are worked out separately from the profits charged to Corporation Tax and are not the accounts profit.
Each group has one allowance of £25 million for a 12-month period, reduced in proportion for a shorter period. The allocating member decides how it is shared between the group’s companies. A company outside any group has the whole allowance.
The tax in box N285 goes to box 497 on the CT600. From there it is included in box 500, the tax chargeable in box 510 and the tax payable in box 525, so it is paid on the same dates as Corporation Tax.
Completing the CT600N in Tax Optimiser
Open the period’s Corp Tax Calculations workspace and choose Property Developer Tax in the Sections menu. The page has four tabs. If the period of account is longer than 12 months it is filed as two returns, each with its own CT600N; use the Return 1 and Return 2 buttons to switch between them.
Step 1 — Enter the calculation (Section 4)
On the Calculation tab, enter the adjusted trading profit or loss (N230 or N235) and any joint venture profit or loss attributed to the company (N240 or N245). Enter losses as positive figures. Then enter any loss relief (N255) and the allowance allocated to the company (N275). All figures are whole pounds.
Tax Optimiser works out the total of profit (N250), the RPD profits (N270), the profits chargeable (N280) and the tax at 4% (N285). A figure that would be negative is shown as nil. If the allowance you enter is more than the whole group could have for a period of that length, a warning appears; it doesn’t stop you filing.
HMRC only accepts a Section 4 that has a profit in N230 or N240. If you enter only losses, Tax Optimiser keeps the figures but tells you they will not be filed, and there is no box 497.
Step 2 — Enter group relief (Section 3)
The Group relief tab has four tables: claims (N95), surrenders (N120), claims for carried-forward losses (N160) and surrenders of carried-forward losses (N190). Click Add company and enter the name, the tax reference and the amount. Enter the other company’s accounting period only if it is different from yours. The tax reference is the 10-digit UTR; if you don’t have it, enter something else that identifies the company, such as its registration number.
The claim totals (N100 and N165) are carried to N260 and N265 on the Calculation tab for you. A claim needs a Section 4, so a company with no profit figure cannot claim.
Each claim has a claim authorisation: tick the box and enter the person authorising and their status. Online returns filed through Tax Optimiser can’t carry copies of notices of consent, so claims must be made under a simplified arrangement and authorised here. Each surrender uses the return itself as the notice of consent: the company details are copied from the return, and the person authorising defaults to the director signing the CT600.
Step 3 — Allocation statement (Section 1), if you are the allocating member
On the Allocation statement tab, tick N5 only if the company is the group’s nominated allocating member. If the statement has already been sent to HMRC, tick N10 and nothing else is needed. Otherwise enter the period the allocation relates to, the ultimate parent company (or tick N35 if that is this company), each company receiving allowance with its accounting period, UTR and amount, and who authorised the statement.
Step 4 — Joint ventures (Section 2), if it applies
On the Joint ventures tab, enter the notional allowance claimed (N70). If allowance is being allocated on behalf of an excluded body, tick N75 and list the allocating companies and amounts (N80), then the excluded bodies that are members of the joint venture (N90).
Step 5 — Save and check the return
Click Save. When the page has something to file, Tax Optimiser:
- ticks box 144 and puts N285 in box 497, which flows into boxes 500, 510 and 525 and the payments shown for the return;
- adds a Residential Property Developer Tax line to the Corporation Tax page of the computation, and a page showing the calculation and every table filed;
- lists the completed form under Supplementary pages on the CT600 Document card, where you can view or download it. Tables with more than seven rows continue on an extra page at the end.
A worked example
A developer with no group has RPD profits of £30 million for a 12-month period and the full £25 million allowance. N230 is 30,000,000, N250 and N270 are 30,000,000, N275 is 25,000,000 and N280 is 5,000,000. N285 is 5,000,000 × 4% = £200,000, which goes to box 497 and is added to the Corporation Tax payable.
CT600N box by box
Boxes N1 to N4 — Company information
The company name, tax reference and the period covered by the page. Tax Optimiser copies them from the return; the period cannot exceed 12 months.
Boxes N5 to N40 — Allocation statement
N5: the company is the nominated allocating member. N10: the allocation statement has already been sent to HMRC for the period; if so, N15 to N65 are left blank. N15 and N20: the period the allocation relates to. N25 and N30: the name and tax reference of the allocating member at the start of the period, if it was a different company. N35: the company is the ultimate parent of the group. N40: the name of the ultimate parent, if N35 is not ticked.
Boxes N45 and N50 — Companies receiving an allocation
For each group company receiving allowance (including the allocating company itself): its name, accounting period, 10-digit UTR and the amount allocated. N50 is the total.
Boxes N55 to N65 — Authorisation of statement
A tick to confirm the statement has been authorised, the full name of the person authorising it and their status.
Boxes N70 to N90 — Joint venture companies
N70: notional allowance claimed. N75: notional allowance is being allocated in respect of an excluded body. N80: each company providing that allocation, with its tax reference (if it has one) and amount; N85 is the total. N90: the excluded bodies that are members of the joint venture company, with their tax references.
Boxes N95 to N115 — Claims to RPDT group relief
N95: each surrendering company, its accounting period if different, its tax reference and the amount claimed. N100 is the total, copied to N260. N105 to N115: the claim authorisation under a simplified arrangement.
Boxes N120 to N155 — Amounts surrendered as RPDT group relief
N120: each claimant company and the amount surrendered to it. N125 is the total. N130 to N155: the details of the company surrendering relief, which make the page the notice of consent.
Boxes N160 to N185 — Claims for carried-forward losses
As N95 to N115, for RPDT losses carried forward by other group companies. N165 is the total, copied to N265. The authorisation also names the authorised company (N175).
Boxes N190 to N225 — Carried-forward losses surrendered
As N120 to N155, for RPDT losses this company has brought forward. N195 is the total.
Boxes N230 to N250 — Profit or loss
N230 / N235: adjusted trading profit or loss. N240 / N245: joint venture profit or loss attributed to the developer. Complete one box of each pair. N250: (N230 + N240) minus (N235 + N245), or nil if that is negative.
Boxes N255 to N270 — Reliefs and RPD profits
N255: allowable loss relief for RPDT losses brought forward. N260: group relief claimed, from N100. N265: group relief for carried-forward losses, from N165. N270: N250 less N255, N260 and N265, or nil.
Boxes N275 and N280 — Allowance and profits chargeable
N275: the allowance allocated to the company for the period. N280: N270 less N275, or nil.
Box N285 — RPDT payable
4% of N280. This figure goes to box 497 on the CT600.
What Tax Optimiser checks, and what it does not do
Before filing, Tax Optimiser checks what HMRC’s validation rejects: a profit and a loss in the same pair; a claim with no Section 4 or no authorisation; a table row with no name, reference or amount; a UTR in N30 or N45 that isn’t 10 digits; an accounting period longer than 12 months, or one that doesn’t overlap the return; an allocation statement with parts missing; N80 rows without N75, or N75 without N80 rows; and a period ending before 1 April 2022.
What it does not do is work out RPD profits. It doesn’t derive them from the accounts, apportion a period that straddles 1 April 2022, carry RPDT losses from one period to the next, apply any statutory limit on loss relief or group relief, or check that the allowance matches the group’s allocation statement. Those figures come from the company’s own working papers.
Common questions
What is the CT600N?
The CT600N is the supplementary page of the Company Tax Return for Residential Property Developer Tax. It records the allocation of the group’s allowance, RPDT group relief and the calculation of the tax. Box 144 on the CT600 is ticked to show it is attached.
What rate is Residential Property Developer Tax?
4% of residential property development profits above the allowance.
What is the RPDT allowance?
£25 million for a 12-month period, reduced in proportion for a shorter period. A group has a single allowance, shared between its members by the nominated allocating member.
Where does RPDT go on the CT600?
The tax in box N285 goes in box 497. It is included in box 500, in the tax chargeable in box 510 and in the tax payable in box 525.
Do I need a CT600N if my profits are below the allowance?
If the company has RPD profits to report, the calculation can be filed with nil tax, and box 497 is then nil. A company that only allocates the allowance or surrenders RPDT losses files the page without a calculation.
When is RPDT paid?
It is treated as Corporation Tax for payment purposes, so it is due on the same dates, including quarterly instalments where they apply.
Can a company with an RPDT loss file the calculation?
Not on its own. HMRC’s return only accepts the calculation when it includes a profit figure. A loss surrendered to another group company is reported in the group relief section instead.
Where to go next
- Corporation Tax in Tax Optimiser — the full journey from trial balance to filed return.
- CT600 box-by-box guide — every box on the main return.
- CT600C: group and consortium relief — the Corporation Tax equivalent of Section 3.
- HMRC’s CT600N guidance — the official notes for every box.