CT600 Tax Return Filing in Porthmadog: Prepare and File Your Company Tax Return with HMRC

A CT600 is the form HMRC uses for a Company Tax Return. It reports a company's Corporation Tax position for an accounting period, setting out income, profits, deductions, reliefs and the resulting Corporation Tax figure, along with details such as the company's registration number and the period covered. It is submitted to HMRC rather than to Companies House, usually alongside the company's accounts and a Corporation Tax computation. The CT600 itself is a summary document — it is the supporting accounts and computation that show how the numbers were arrived at.

A company normally needs to file a Company Tax Return if HMRC has sent it a notice to deliver one, or if it has taxable profits, chargeable gains or other circumstances that bring it within the charge to Corporation Tax. This is not limited to large businesses: small and micro companies can also be required to file. Whether a particular company must file, and for which periods, depends on its own circumstances, so it is worth checking your position rather than assuming that being small means you are outside the system.

Yes, they are two separate filings with two different recipients. Statutory accounts are prepared under the applicable accounting framework and filed with Companies House as part of the public record. The CT600 is a tax return submitted to HMRC to report the company's Corporation Tax position. Filing accounts at Companies House does not discharge your Corporation Tax filing obligation, and filing a CT600 does not satisfy your Companies House obligations. The figures may overlap heavily, but the purposes and the rules behind each document are different.

No — the computation and the return do different jobs. The Corporation Tax computation is the working that starts with the accounting profit shown in your accounts and makes the adjustments needed to reach taxable profit and the resulting Corporation Tax liability. Typical adjustments might include adding back expenditure that is not allowable for tax, removing depreciation and claiming capital allowances instead, or bringing in losses and reliefs. The CT600 is the return form on which the resulting figures are reported to HMRC. In practice the two travel together, which is why a return prepared without a proper computation can be difficult to stand behind.

A CT600 is normally submitted together with accounts and a computation for the period, because HMRC needs to see how the figures in the return were calculated. That means the accounts used for tax purposes need to exist even where they are straightforward. It is also worth remembering that the accounts attached to a Company Tax Return and the accounts filed at Companies House are separate submissions, even when they are based on the same records, and each has its own deadline and format requirements.

We normally work from your bookkeeping records or trial balance, the accounts for the period, and details of anything that affects the tax position — income and expenses, capital purchases, asset disposals, loans and director's loan account movements, losses brought forward, and any reliefs you intend to claim. Your company's unique taxpayer reference, registration number and accounting period dates are also needed for the return itself. Having last year's return and computation to hand is helpful too, as it makes carry-forward figures and previous adjustments much easier to follow.

Accounting profit comes from your accounts and is prepared under an accounting framework. Taxable profit is a tax concept, so the two can differ. The computation usually starts with accounting profit and then adjusts it: adding back expenditure that is not allowable as a business deduction, removing items of income that are not taxable, taking out depreciation and claiming any capital allowances due, and applying brought-forward losses or reliefs where available. Once taxable profit is established, Corporation Tax is worked out on it. Because rates, thresholds and reliefs change and depend on the company's circumstances, we apply the rules as they stand for the period in question.

No, these are two distinct obligations. Filing is about submitting the Company Tax Return and its supporting documents to HMRC by the relevant date. Paying is about settling whatever Corporation Tax is due, which is handled separately and can fall on a different date. It is quite possible for a company to have a filing obligation but no tax to pay, and equally possible to have tax to pay before the return is filed. Keeping both dates on the radar — and keeping money aside if a liability is likely — is one of the simplest ways to avoid unnecessary pressure later.

HMRC operates its own penalty and interest regime for late Company Tax Returns, and charges can build up where a return remains outstanding. The exact consequences depend on the circumstances of the filing and how long it is delayed, so we would always rather help you file on time than deal with the fallout afterwards. If you are behind, the practical step is to get the position established and the return prepared as quickly as the information allows, and to keep HMRC informed while that happens.