What You Can File

id: what-you-can-file title: What You Can File category: getting-started tags: [what does tinytax do, file CT600, file accounts, both HMRC and Companies House, submit CT600 and accounts, corporation tax online, HMRC closing, alternative to HMRC, replacement filing service, software only, what can I file, getting started, overview] applies_to: [all] difficulty: beginner last_updated: 2026-02-24 related: [filing-your-first-ct600, supported-company-types-and-features, company-size-eligibility, getting-started-dashboard]

@AdamsWinter files your corporation tax return (CT600) to HMRC and your statutory accounts to Companies House — both from one form.

What's Included

When you complete a filing through @AdamsWinter, you get:

CT600 corporation tax return — submitted electronically to HMRC
Statutory accounts — submitted electronically to Companies House (micro-entity or small company format)
Tax computation — generated automatically from your figures

All three documents are created from the same set of figures. You enter your numbers once, and @AdamsWinter generates everything.

Filing Options

You can choose what to file based on your needs:

Option	What's filed	When to use
CT600 and Accounts	Both HMRC and Companies House	Most common — covers everything
CT600 only	HMRC only	If you file accounts separately (e.g., through an accountant)
Accounts only	Companies House only	For LLPs and companies that file CT600 elsewhere

Select your filing option from the dashboard when you start a new filing.

Who Can Use @AdamsWinter

@AdamsWinter supports:

Private limited companies (Ltd) — trading, property, dormant, or mixed income
Companies limited by guarantee (CLG)
Limited liability partnerships (LLP) — accounts only
Charities and clubs — CT600 only, via manual entry

For a full list of supported company types and tax features, see our supported features guide.

Size limits: Any company can file CT600 regardless of size. Accounts filing requires your company to qualify as a micro-entity or small company. See our company size guide for thresholds.

Switching from HMRC's Filing Service

If you previously filed your CT600 through HMRC's Corporation Tax Online service, @AdamsWinter is a direct replacement. HMRC is moving to software-only filing, which means you'll need third-party software like @AdamsWinter to submit your returns.

To get started, search for your company number on the dashboard. @AdamsWinter fetches your company details from Companies House automatically.

ℹ Your previous filing history with HMRC is not affected. @AdamsWinter submits new returns — it doesn't change anything you've already filed.

How It Works

Add your company — search by company number or enter details manually
Select your period — @AdamsWinter detects your next filing period automatically
Enter your figures — turnover, expenses, balance sheet
Preview — review your CT600, accounts, and tax computation
Submit — filed electronically to HMRC and Companies House

For a detailed walkthrough, see our step-by-step filing guide.

Common Questions

Is @AdamsWinter free?

No. Filing requires a subscription. See our pricing page for current plans.

Can I file a late return?

Yes. @AdamsWinter can file CT600 returns for any period, including late filings. HMRC may charge penalties for late submission, but @AdamsWinter doesn't restrict when you can file.

Do I need an accountant?

No. @AdamsWinter is designed for company directors filing their own returns. If your company has straightforward finances (trading income, standard expenses, no complex tax reliefs), you can handle it yourself.

What if my company is dormant?

@AdamsWinter supports dormant company filings. Select "Dormant" as your company type and the form simplifies to just the essentials. See our dormant filing guide.

Ready to Start?

Add your company to the dashboard and begin your first filing.

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