ByteLogic CT600 Help

ByteLogic CT600 helps UK limited company directors prepare a Corporation Tax return package, review the documents, and submit to HMRC after payment.

Dashboard Prepare CT600 Submission status Pricing
Draft first, pay later. You can enter figures and review the generated package before Stripe checkout appears. Payment is only requested when you submit the return to HMRC.

Overview

The filing flow has three stages: enter details, review documents, then pay and submit. The review package contains the CT600 XML, accounts iXBRL, computations iXBRL, and a manifest of what will be sent.

Company details

Start with the company name or Companies House number. You will also need the Corporation Tax UTR, accounting period dates, director name for the declaration, and average number of employees for the accounts information.

CT600 figures

Enter the income, expense, balance sheet, and tax adjustment figures from reviewed accounts. These are filing inputs used to build the CT600 attachments, not a separate bookkeeping product. ByteLogic calculates total income, total expenses, profit before tax, taxable profit, Corporation Tax payable, net assets, and shareholders' funds.

  • Use positive numbers in the fields. Expense rows are treated as deductions.
  • Use the disallowable expenses field for costs that should be added back for tax.
  • Use capital allowances where they reduce taxable profit.
  • Check the balance sheet warning before submitting.

Review package

Generate the draft package before paying. Download the package and check that the period, UTR, company number, tax payable, accounts attachment, and computation attachment are correct.

Pay and submit

When you choose to submit to HMRC, unpaid accounts are sent to Stripe Checkout for the CT600 annual plan. After payment, ByteLogic returns to the CT600 submission flow.

Status checks

If HMRC returns a pending status, ByteLogic stores the correlation ID. You can leave the page and return to CT600 Status later to poll HMRC again using the same correlation ID.

Current scope

The first ByteLogic CT600 release is for straightforward UK limited company self-filers. It supports CT600 production, iXBRL accounts and computations, extended accounting period splits, Company Type 11, and later HMRC status polling.

VAT MTD, PAYE RTI, payroll, invoicing, bank feeds, Companies House filing, amendments, Test in Live for customers, and specialist supplementary pages are outside the first customer-facing CT600 release.