Help Centre · Corporation Tax · 2 min read

Submitting to HMRC and Companies House

Sign the accounts, clear the pre-flight checks, and file to HMRC and Companies House through the guided wizards.

Tax Optimiser Updated 12 Jun 2026

With the computation reviewed and the accounts finished, two filings remain: the CT600 with accounts and computation attached goes to HMRC, and the (usually filleted) accounts go to Companies House. Both run as guided wizards from the period menu.

One payment unlocks both filings

The first time you open either submission for a period you're asked for the per-period submission fee. A single payment, made securely through Stripe, unlocks both the HMRC and Companies House filings for that accounting period.

The secure checkout page for the per-period submission fee

Before you can send

The wizards start by checking the period is actually ready, and list anything outstanding with a button next to each item:

  • Take the accounts out of draft — and sign them: the Sign Accounts action in View Accounts records the approval, and the director signage date is set alongside.
  • Companies House authentication code — the 6-character code Companies House posts to the registered office (the How to obtain link covers requesting one).
  • Presenter ID and password — your Companies House presenter account for software filing (How to apply explains the one-off registration). Accountant firms set this once at firm level.
  • Government Gateway credentials — for the HMRC side, entered in Organisation settings.
The corporation tax submission errors step listing outstanding requirements such as draft accounts and signage date The sign accounts preview used to record director approval

The HMRC wizard

Corp Tax Submission walks five steps: Errors, Verification, Review Document, Review Calculation and Send Tax Return. Verification asks you to confirm the client has approved the accounts; the two review steps embed the final accounts and computation for a last read; the send step confirms the company type and the director accepting the declaration, then transmits the CT600 with iXBRL accounts and computation attached to HMRC.

The verification step of the corporation tax submission wizard The review document step showing the final accounts embedded in the wizard The send tax return step with company type and the director accepting the declaration

The Companies House wizard

Companies House Submission follows the same shape — validation, verification, review, send — filing the filleted accounts electronically. Companies House processes electronic filings in minutes to hours, and the submission status on the period overview tracks acceptance automatically.

The Companies House submission requirements step showing auth code, presenter details, signage date and draft status

After sending

Each submission gets a receipt and its status is polled until HMRC or Companies House accept (or reject, with reasons shown). Once accepted, the period can be locked from the Overview so the filed numbers can't drift, and the dashboard deadlines update to the next period. If something needs correcting after acceptance, Mark as amended starts an amended filing from the same data.

The short version

Submitting to HMRC and Companies House — in brief

A single per-period fee paid through Stripe unlocks both filings. The wizards pre-check everything: accounts out of draft and signed, director signage date, Companies House auth code and presenter credentials, Government Gateway login.

The HMRC wizard reviews the final accounts and computation before sending the CT600 with iXBRL attachments. The Companies House wizard files the filleted accounts the same way.

Receipts and acceptance are tracked automatically; lock the period once accepted, and use Mark as amended if a correction is ever needed.