Preparing information for a company tax return

A Company Tax Return needs more than a bank balance and a profit estimate. Prepare the final accounts, detailed ledger and evidence for tax adjustments and claims. Confirm the tax period and identify unusual transactions before the computation is finalised.

Give the accountant information about assets, loans, remuneration, dividends, donations, losses and overseas activity where relevant. Keep a list of questions and missing documents. A director's explanation can help establish facts, but it should be distinguished from documentary evidence and a concluded tax treatment.

Start with final accounting evidence and the right period

Confirm the company, tax period and accounts used for the return. Obtain the final trial balance and adjustment schedule, not an earlier management report whose figures later changed. HMRC explains the Company Tax Return's role in calculating taxable profit and the liability. ^[1] Keep the accounting source and tax computation connected so material differences can be traced and approved.

Provide detailed ledger information and reconciliations for balances affecting tax. A total expenses figure may conceal entertaining, capital purchases or connected-party payments requiring separate review. Identify unusual transactions before the computation is finalised. The accountant needs facts and documents, not only a suggested tax category selected by someone trying to complete a bookkeeping screen quickly.

Prepare schedules for adjustments and claims

Supply asset additions and disposals with dates, invoices, finance arrangements and use. Keep director loans, remuneration, dividends and related-party movements separately explained. Provide donation records, losses brought forward and overseas income evidence where relevant. Do not assume that an item omitted from a standard questionnaire is automatically irrelevant to the company's tax position.

Use Capital expenditure and tax treatment for capital expenditure and Losses in a limited company for loss records. For each claim, identify the applicable conditions, evidence and deadline with the adviser. A commercially successful project or a large purchase does not automatically qualify for a tax relief. Keep uncertain eligibility visible until it has been assessed, rather than entering the most favourable amount and planning to justify it later.

Distinguish facts, estimates and professional judgements

Label missing documents and explain efforts to obtain them. Keep estimates with their method and supporting information. A director's recollection can help establish facts but should not be presented as a supplier invoice or formal agreement. Where the treatment depends on a technical judgement, identify the question clearly and provide the underlying transaction details.

Review significant changes from earlier years. A new activity, ownership change, loan arrangement or accounting policy can affect tax work even if the ledger categories look familiar. Supply the prior computation and relevant elections or claims so the adviser can track continuing positions. Avoid assuming every brought-forward figure is correct merely because it appeared in the previous software file.

Organise approval and submission evidence

Agree who answers queries and who approves the completed return. Provide directors with a concise explanation of material adjustments, claims and remaining uncertainty. Approval should relate to the actual final version. If figures change after approval, identify whether renewed review is needed rather than submitting a materially different computation under an earlier general instruction.

Use the current filing route. The former joint HMRC service closed in March 2026, and current guidance explains commercial software and the limited alternatives. ^[2] Check that required accounts, computations and any separate claim information are submitted as appropriate. A successful upload or saved document is not the same as accepted filing; retain the relevant receipt and status evidence.

For Corporation Tax record review, deliver an indexed pack with a gap list and the intended timetable. Ask for the estimated tax and payment plan early enough to arrange funds separately from return filing. After completion, keep the final return, computation, evidence and acceptance record together. Use recurring queries to improve the next year's bookkeeping, particularly where missing purpose or ownership information repeatedly delays tax decisions.

Label estimates before they reach the computation

A director may provide an estimated project cost or an approximate split of business use while records are still being collected. Mark the figure clearly, explain its basis and identify what evidence could confirm it. Do not let an estimate become indistinguishable from a verified ledger balance as the preparation file moves between people.

Agree with the accountant how each unresolved figure will be handled before approval. Record any later replacement and its effect on the calculation. Keep factual explanations separate from conclusions about deductibility or relief, which may require professional judgement. This lets the reviewer assess the quality of the evidence and avoids a return that appears precise while relying on assumptions nobody has consciously accepted or documented for the relevant period.

Illustrative scenario

A company sends its trial balance but omits a schedule of equipment sold during the year. The tax review identifies the missing disposal information and requests proceeds and purchase history. Completing the evidence before filing avoids treating the asset position as unchanged simply because the ledger description is brief.

Preparation checklist

• Confirm final accounts and the tax accounting period.
• Prepare schedules for adjustments and material claims.
• List unusual transactions and connected parties.
• Resolve questions and retain approval of the final return.