Filing for clients from Tax Optimiser splits neatly in two: things you set up once for your firm, and things you do per client. Get the firm side right first and every subsequent filing — statutory accounts to Companies House, the CT600 to HMRC — reuses it automatically.
Once per firm
- Companies House Presenter ID and password — your firm’s software-filing account with Companies House, entered on the Companies House tab of Firm Settings.
- HMRC Sender Id and password — your firm’s Government Gateway login, entered on the HMRC tab. Once saved, it files Corporation Tax for every client as their agent.
- Credits — firms pay for filings with credits rather than a per-period fee; one credit covers a period’s filings to both Companies House and HMRC.
The detail, including how to obtain a Presenter ID, is in Firm settings for filing.
Once per client
- Create the organisation — either straight from the Companies House register by searching the company name, or by name only (sole traders, partnerships, or companies you’ll complete manually). See Adding a client organisation.
- Complete the company record — Companies House number, authentication code and Corporation Tax UTR. The period’s Setup Process Checklist tracks what’s still missing.
- Prepare the period — trial balance, accounts and the Corporation Tax computation. See Preparing the period for the map through all three stages.
Then, for every period
Two guided wizards do the filing: accounts to Companies House and the CT600 to HMRC. Both check the same pre-flight list — credentials, authentication code, signed accounts — and both draw on your firm-level settings, unless a client has their own (see Whose credentials file what).
Next: Firm settings for filing: Presenter ID and Government Gateway.
