Corp tax over ride

Good question — this is a common source of confusion, and the short answer is that TinyTax is handling it correctly, even though it looks alarming at first glance.

Here's what's happening:

Bank interest is classified as non-trading income (it goes into Box 170 of the CT600), and TinyTax does include it in the tax calculation. However, the system then nets your expenses against all income. If your total expenses exceed your total income — meaning the company is at an overall loss — the taxable profit (Box 315) will come out as zero, and no corporation tax will be due.

The reason manually typing zero into the income field doesn't work is that TinyTax recalculates everything from your entered figures automatically. You can't override the calculation directly — the way to get zero tax is to make sure all your expenses are entered correctly so the net result is a loss.

A few things to check:

1. Are your admin and setup expenses entered in the correct section of the P&L? They need to be captured in the form (not just visible in your own accounts) for TinyTax to include them in the calculation.
2. On the Tax Computation tab or review page, check what TinyTax shows as the taxable profit (Box 315). If your expenses are correctly entered and exceed your bank interest, Box 315 should show zero and there will be no tax to pay.
3. If Box 315 is showing a positive figure despite your expenses, it usually means some expenses haven't been entered yet, or they've been entered in a field that doesn't feed into the CT600 calculation correctly.

If after checking your entries Box 315 still shows a profit when it shouldn't, post back here with the figures and we can take a closer look.

Apologies — my earlier reply got this wrong, and I want to set the record straight.

You are correct: corporation tax of £70.30 is being charged on the £389 of bank interest, even though your overall accounting loss is £370. That is *not* what my previous reply implied, and it is *not* a bug in the underlying calculation — but the input page was misleadingly showing Box 315 as zero, which I have just fixed (more on that below).

**What is actually happening with the tax**

For a property company in its first year, the £759 of admin and set-up expenses creates a UK property business loss. For CT600 purposes, current-year property business losses cannot be set against non-property income (your bank interest) within the same accounting period — there is no element in the HMRC CT600 XML schema for reporting that in-year offset. The property loss has to be carried forward instead, and you will see it in Box 805 (UK property business losses carried forward) on the review page. Once you do start receiving rental income, that brought-forward loss can then offset it.

So in this period:
- Box 170 (non-trading income / interest) = £389
- Box 315 (profits chargeable to CT) = £370 (after small-pound rounding)
- Box 440 (CT payable) = £70.30
- Box 805 (property losses carried forward) = £759 — preserved for future years

**The UI bug I just fixed**

The input page was incorrectly showing Box 315 as zero while simultaneously showing £70.30 of CT — which made it look broken even though the underlying calculation was correct. The review page and PDF were always showing the right figure (£370). I have deployed a fix so the input page now matches: Box 315 will show £370, in line with the CT figure. If you reload the form, you should see the consistent values.

**Sorry again for the confusion** in my first reply. The way I described it was simply wrong for a property company with bank interest. If you have any further questions or want a closer look at the figures, post back here.

Hi Richard,

Thanks for coming back on this — and apologies for the moving target. We made a substantive change to how property losses are treated yesterday, and your filing was caught between two versions of the rules. Let me explain where things stand now.

**What changed**

After your previous post, our tax adviser confirmed that for a UK property company in the same accounting period, current-year property business losses *must* be set against same-period non-property income (such as bank interest) under CTA 2010 s.62 — automatically, not as an elective claim. That contradicts what I said in my earlier reply. The fix has been deployed.

That is why the corporation tax now shows zero on your return: your £833 of property expenses is offsetting your £390 of bank interest in-year, leaving £443 of unused property loss to carry forward to future periods.

**A second important change**

Today we also added a question to the property-company branch of the form, asking whether your property business has actually started letting yet. This matters because:

- If you have let property to a tenant (in this accounting period or any earlier one), your business is "commenced" for tax purposes. The £0 corporation tax above is correct, and the £443 unused loss carries forward.
- If you have *not* yet let any property, your costs are pre-commencement expenditure under HMRC PIM2505. They are not a current-year property business loss — they are deferred until the period your first tenant moves in. In that case the corporation tax on £390 of interest would be £73.91, and the £833 of expenses would be tracked as pre-commencement to be deducted in the year your first tenant arrives.

**What you need to do**

Please reload the submission form. You should now see a banner above the P&L block describing your commencement status, with a one-click link to flip it if our default is wrong:

- If you have already let property → click "Ive already let a property" and the £0 result is yours.
- If you have not yet let property → leave the banner default. The CT will revert to roughly £74 and your £833 of expenses will be parked as pre-commencement.

The form question and how it works is explained in detail at https://tinytax.co.uk/support/property-business-commencement.

**On adding your own corporation tax**

Please dont — the calculation is now doing the right thing for whichever commencement state you confirm. Manually overriding the CT figure would file the wrong amount with HMRC. If your gut says the figure looks wrong, the answer is to check the commencement question, not override the result.

Once again, sorry for the back-and-forth — the underlying tax point was genuinely wrong on your first reply and the platform has been corrected for you and everyone else. If anything is still unclear after you reload the form, post back here.

Really glad it all clicked — thanks for bearing with us through the back-and-forth on this one. Good luck with the filing!