Pay as you go CT600 filing: £10 + VAT, only when you submit

Tax Optimiser is pay as you go CT600 software. It is free to sign up and prepare your company tax return, and you pay £10 + VAT (£12) only when you are ready to submit. That one payment covers the CT600 filed to HMRC and your accounts filed to Companies House. There is no subscription and no annual licence: you pay per return, when you file it.

Get started - free trial

How pay as you go works

Sign up free. Create your account and add your company. No payment is taken.
Prepare your accounts and CT600 free. Pull your trial balance from Xero or QuickBooks, or upload your own. Build the accounts and the tax computation and preview every document before you pay anything.
Pay when you submit. The first time you open the submission for the period you pay £10 + VAT by card, Apple Pay or Google Pay through Stripe.
File to HMRC and Companies House. Both filings go directly from Tax Optimiser. If a return is rejected, or you need to amend it later, you send it again at no extra charge.

What one £10 + VAT payment covers

CT600 corporation tax return and tax computation, filed directly to HMRC
Statutory accounts filed directly to Companies House, with automatic iXBRL tagging
Micro-entity (FRS 105) and small company (FRS 102 Section 1A) accounts
Two-way Xero and QuickBooks sync, or upload your own trial balance
Resubmissions and amended returns at no extra charge
A period longer than 12 months, including both of its CT600 returns

The fee is per company for each accounting period, which for most companies means once a year. See everything the software does on the Corporation Tax feature page.

Pay as you go CT600 vs an annual subscription

Most company tax return software is sold as an annual plan or as an add-on to a bookkeeping subscription. A company files one CT600 a year, so pay as you go means you pay for exactly that and nothing else.

	Pay as you go (Tax Optimiser)	Annual subscription
When you pay	When you submit the return	Typically up front for the year
Renewal	None. Nothing renews	Renews each year until you cancel
A year with nothing to file	£0	Usually still charged
Trying it first	Prepare the whole return free	Depends on the provider

For provider-by-provider prices, see our CT600 and company accounts price comparison.

Who pay as you go suits

A single company filing its own year end. One return a year, one payment a year.
Directors filing without an accountant. Check the figures and the finished documents before you commit to paying.
Companies that used HMRC's free filing service. It closed on 31 March 2026, so a CT600 now has to be filed with commercial software. Pay as you go keeps that to one small fee a year.
Dormant companies. Dormant accounts and the CT600 are £5 + VAT. See dormant company filing.

Accountants: pay as you go or credit packs

Accounting firms can also pay as you go, buying a single credit at £10 + VAT for one client's accounts and CT600. Firms filing for many clients can buy credit packs instead, which bring the cost down to as little as £3 + VAT per company. Credits do not expire. See accountant pricing.

Frequently asked questions

Is there a subscription or annual licence for filing a CT600?: No. Filing a CT600 with Tax Optimiser is pay as you go: £10 + VAT (£12 including VAT) per company for each accounting period, with no subscription, no annual licence and nothing to cancel. If you do not file in a year, you pay nothing.
When do I pay?: Only when you are ready to submit. It is free to sign up, enter your figures, build the accounts and tax computation and preview every document. You are asked to pay the first time you open the Corporation Tax or Companies House submission for the period, by card, Apple Pay or Google Pay through Stripe.
Do I pay again if HMRC rejects my return or I need to amend it?: No. The one payment for the period covers resubmissions after a rejection and amended returns, at no extra charge.
Is filing my accounts to Companies House included?: Yes. One payment covers both the CT600, tax computation and iXBRL accounts sent to HMRC and the statutory accounts filed with Companies House for that accounting period.
What if my accounting period is longer than 12 months?: A period of accounts longer than 12 months needs two CT600 returns, but it counts as one period, so the single £10 + VAT fee covers both returns.
What does a dormant company pay?: £5 + VAT (£6 including VAT) for the period, covering the dormant accounts and the CT600, on the same pay as you go basis.
What if I have more than one company?: Each company pays £10 + VAT for each period it files, with no minimum and no per-user fee. Accountants and anyone filing for many companies can buy credit packs instead, which bring the cost down to as little as £3 + VAT per company.

File your CT600 pay as you go for £10 + VAT

Free to prepare. Pay only when you submit. Covers HMRC and Companies House, with no subscription.

Get started - free trial