Why Are Some CT600 Boxes Empty or Zero?

When you preview your CT600, you may notice that many boxes show as zero or empty. This is normal — a CT600 has over 200 boxes, but most companies only use a small number of them. This guide explains which boxes apply to your situation and why others are blank.

Which Boxes Apply to Your Company Type?

The CT600 has separate sections for different types of income. Only the boxes relevant to your company type will be populated. The rest are correctly left at zero.

Company Type	Income goes to	Loss/Profit box	Boxes that will be zero
Trading	Box 145 (Turnover from trade)	Box 165 (profit) or Box 780 (trading loss)	Box 190, Box 250, Box 805 (property boxes)
Property	Box 190 (Net property income)	Box 190 if profitable, Box 805 if loss	Box 145, Box 155, Box 160, Box 165, Box 780 (trading boxes)
Mixed Income	Box 145 AND Box 190	Box 165 and/or Box 190	Depends on which income types you have

Common Reasons for Empty Boxes

Box 3 (Tax Reference / UTR)

Box 3 is always blank in the preview. Your UTR is entered when you click Submit Corporation Tax — a popup asks for your UTR and Government Gateway credentials at that point. The preview is a draft; Box 3 gets filled automatically at submission.

Box 4 (Company Type Code)

Box 4 shows a numeric code identifying the company's legal structure for HMRC purposes. Most standard UK limited companies show 0, which means "none of the listed special categories apply." This is correct even for property investment companies.

The codes used by HMRC are for specific legal structures, not general business activities:

Code	Meaning
0	Standard UK limited company (default — applies to most companies)
2	Close investment-holding company (CIHC)
6	Members' club or voluntary association
7	Property management company (companies that manage property on behalf of others)
8	Charity or owned by a charity

Code 7 is not for general property rental companies. A company that owns property and collects rent directly is a standard limited company (code 0). Code 7 applies to a narrow category of companies that manage residential properties on behalf of freeholders or third-party landlords — charging management fees rather than receiving rent. If you have seen code 7 on a previous CT600 filed by different software or an accountant, it may have been an error.

HMRC identifies whether your company has property income from the CT600 content itself — Box 190 populated and Box 145 blank clearly indicates a property company. Box 4 = 0 does not mean "trading company"; it just means no special category applies.

Box 145 (Turnover from Trade)

Box 145 is blank if:

• Your company type is set to Property Company — rental income is reported in Box 190, not Box 145. Box 145 is for trading turnover only.
• Your company type is set to Dormant — dormant companies have no turnover
• You haven't entered a turnover figure in the P&L section yet

Box 165 (Net Trading Profits)

Box 165 shows zero if:

• Your company made a trading loss this period — losses are reported in Box 780 instead
• Your company type is Property or Dormant

Box 190 (Net Income from Property)

Box 190 shows zero if:

• Your company type is set to Trading — trading income goes to Box 145, not Box 190
• Your company type is Property but you haven't entered a property income figure
• Your property business made a loss this period — when rental expenses exceed gross rent, the net property income is negative and Box 190 shows zero. The loss amount is recorded in Box 805 (UK property business losses) and carried forward.

Box 780 (Trading Losses) vs Box 805 (Property Losses)

These are separate boxes for different types of loss:

• Box 780 — losses from a trading business only. Always zero for property companies.
• Box 805 — losses from a property business. Shows the loss to carry forward when rental expenses exceed rental income.

If your company is set up as a Property Company and Box 780 is populated instead of Box 805, regenerate the preview to refresh the calculations.

Boxes 155, 160 (Trading Losses Brought Forward)

These show zero unless your company has trading losses brought forward from a previous period.

Boxes 345, 350, 355, 360, 365 (Tax Calculation)

These show zero when your company has no taxable profit — for example, during a loss period. No profit means no corporation tax to calculate.

Loss Periods — Why Most Boxes Are Zero

If your company made a loss, the CT600 will have very few populated boxes. This is correct.

For a trading company in a loss period:

• Box 145 shows your turnover
• Box 780 shows the trading loss carried forward
• Tax boxes are zero (no tax to pay)

For a property company in a loss period:

• Box 145 is zero (correct — you are not a trading company)
• Box 190 is zero (correct — net property income is negative, so this box shows zero)
• Box 805 shows the property loss carried forward
• Box 780 is zero (correct — that is for trading losses only)
• Tax boxes are zero (no tax to pay)

The key figures in a property loss period are: your gross income and expenses (in the accounts), the carried-forward loss in Box 805, and zero tax. Everything else being zero is expected.

How HMRC Sees Your Full Income

The CT600 form reports net figures — Box 190 shows net property income (gross rent minus expenses), and if expenses exceed rent, Box 190 is zero. This can look like your gross rental income is missing.

In practice, HMRC receives two documents when you file:

1. The CT600 — shows the tax position (net income or loss, tax calculation)
2. The iXBRL accounts — your full profit and loss account, including gross rental income and a breakdown of all expenses

Your gross rental income is clearly visible in the accounts. HMRC has the complete picture.

Checking Your Figures Are Correct

If you are unsure whether your CT600 is complete:

1. Check your company type — make sure it matches your business activity (Trading, Property, or Mixed Income)
2. Check the P&L section — all your income and expense figures should be entered and saved
3. Regenerate the preview — return to the preview page to see the latest CT600 with your saved figures
4. Look at the right boxes — trading income in Box 145, property income in Box 190 (net), property losses in Box 805

Common Questions

Q: My CT600 preview is mostly empty — is something broken? A: Almost certainly not. A CT600 for a simple company typically only populates 10–15 boxes out of 200+. Loss periods have even fewer. If your income and loss/profit figures are showing in the correct boxes for your company type, your filing is complete.

Q: I have property income but Box 190 is zero — what does that mean? A: For a property company, if your rental expenses exceeded your gross rent this year, the net property income is negative — so Box 190 will be zero, and the loss goes to Box 805 instead. This is correct HMRC treatment. Your gross rent is still visible in the iXBRL accounts filed alongside the CT600.

Q: Box 145 shows my figures but Box 190 is empty — is that right? A: Yes, if your company type is Trading. Box 145 is for trading turnover and Box 190 is for property income. A trading company with no property income will always show Box 190 as zero.

Q: My company made a loss — why is the tax section all zeros? A: Because there is no corporation tax to pay when there is no taxable profit. Your loss is recorded in Box 780 (trading) or Box 805 (property) and carries forward to offset future profits. The zero tax boxes are correct.

Q: My previous CT600 showed Box 4 = 7, but now it shows 0 — which is correct? A: Code 0 is correct for standard UK limited companies, including property investment companies. Code 7 ("property management company") is a specific HMRC category for companies that manage properties on behalf of third parties. If your company owns property and collects rent directly, code 0 is right. The previous code 7 may have been an error by your previous accountant or software.

Last updated: April 2026