# Taxley

> Taxley is UK Corporation Tax filing software from Taxley UK LLP (LLP number OC461735, England and Wales) that lets directors of small limited companies prepare their own CT600 and iXBRL accounts, file the return to HMRC and file the accounts at Companies House.

Taxley at taxley.co.uk is a UK business and is not connected with taxley.com (a US tax-resolution business), Taxly or any other similarly named business.

## What Taxley does

- Prepares the CT600 Company Tax Return (with CT600A for loans to participators, CT600C for group relief, and the full CT600E supplementary pages for charities and community amateur sports clubs), micro-entity (FRS 105) or small-company (FRS 102 Section 1A) accounts and the tax computation in iXBRL.
- Files the return live to HMRC using the company's own Government Gateway login.
- Files your annual accounts at Companies House: live since 28 September 2026, for micro-entity, small, abridged and dormant accounts prepared in Taxley, at no extra cost. Once the return is paid and the accounts are finished, you press "File accounts at Companies House" on the filing page; you need the company's 6-character Companies House authentication code.
- Applies the main rate, the small profits rate and marginal relief, including associated companies and short accounting periods. It also files returns for older years, back to accounting periods that started on 1 April 2020. Profits before 1 April 2023 are taxed at the single 19% rate (FY2020 to FY2022), and a period straddling 1 April 2023 is split, with marginal relief on the later part. For those older periods the capital allowances are entered, not calculated, and the super-deduction isn't claimed.
- Splits a first period of account longer than 12 months into two accounting periods and prepares two CT600 returns.
- Carries trading losses, UK property business losses and non-trading loan relationship deficits forward and sets them against profits, and carries a trading loss back against the profits of the previous 12 months (CTA 2010 s.37), claimed in the loss-making period's return. When a return uses losses brought forward, the computation states the company's deductions allowance (CTA 2010 s.269ZZ): £5 million for a 12-month period, less for a shorter one.
- Calculates capital allowances for most claims (the annual investment allowance, main and special rate pools, full expensing, the zero-emission car first-year allowance, and structures and buildings allowance) and chargeable gains for most sales of UK property and shares bought in one go, including indexation and the substantial shareholding exemption.
- Works out section 455 tax on a director's or other participator's loan that's still outstanding, and the relief due when it's repaid. It supports group relief (claims and surrenders) between UK companies in a 75% group, and overseas interest, dividends and property income with double taxation relief for foreign tax already paid.
- Offers a one-page Simple mode for straightforward micro-entity returns, alongside the Advanced step-by-step editor and the box-by-box Full CT600 view, dedicated routes for dormant companies and charities (CT600E), and an agent mode for accountants filing for clients.
- Amends a return filed with Taxley once HMRC has accepted it, normally within 12 months of the filing deadline, for the standard fee for a return of that kind. An amended return goes to HMRC. If that period's accounts aren't at Companies House yet, you can file the amended accounts there from the same page. Taxley doesn't file revised accounts for a period Companies House already has.
- Accepts your own iXBRL accounts file in place of Taxley's, checked against the return before filing to HMRC. Taxley doesn't file uploaded accounts at Companies House; you file those there yourself. You can download PDF copies of the CT600, the accounts and the tax computation, marked as drafts until the return is filed.
- Charges one fee per return, shown before you pay and charged only when you choose to file. The fee also covers filing the company's annual accounts at Companies House, which charges no fee for annual accounts. Preparing and previewing is free; there is no subscription, and you don't need an accountant to file, though Taxley isn't tax advice and you should review your figures before you file, ideally with a qualified adviser. No VAT is charged on Taxley's fees.

## What Taxley doesn't do

- Confirmation statements (CS01): Taxley doesn't file the confirmation statement, so you file it yourself on Companies House's online service. Taxley does file your annual accounts there, except three kinds you file yourself: accounts you uploaded instead of Taxley's, accounts for a period Companies House already has (whether filed elsewhere or revised), and first accounts when the return's period doesn't start on the company's date of incorporation.
- It doesn't calculate deferred tax, or capital allowances and chargeable gains outside the calculators' scope (for example leasing, freeports and the VAT capital goods scheme; or assets other than UK property and shares bought in one go, sales to someone connected with the company, or reliefs such as rollover) — those still need a figure you work out yourself.
- Not supported: consortium relief and group relief with companies outside the UK; R&D tax relief, creative industry reliefs and the patent box; bed-and-breakfasted director's loans unless repaid entirely by a credited dividend, salary or bonus; overseas branches and controlled foreign companies; terminal loss claims and the temporary three-year carry-back for losses of periods ending between 1 April 2020 and 31 March 2022; losses brought forward used by a company in a group, or above the deductions allowance; charities and community amateur sports clubs (CASCs) that are only partly exempt; quarterly instalment payers, medium-sized or audited companies; intangible assets and special regimes; non-resident companies and companies in liquidation or administration; accounting periods that started before 1 April 2020; VAT returns, Self Assessment and Making Tax Digital for Income Tax.
- It is software, not an accountant or tax agent: it doesn't give tax advice and doesn't pay the company's Corporation Tax.

## Key pages

- [Pricing](https://taxley.co.uk/pricing): the fee per return, which also covers filing the accounts at Companies House
- [How it works](https://taxley.co.uk/how-it-works): the filing workflow step by step
- [Check if Taxley fits your company](https://taxley.co.uk/check): a few quick eligibility questions
- [Corporation Tax calculator](https://taxley.co.uk/corporation-tax-calculator) (main rate, small profits rate and marginal relief) and [Corporation Tax deadline calculator](https://taxley.co.uk/corporation-tax-deadline-calculator) (payment, CT600 and Companies House dates)
- [Free tools](https://taxley.co.uk/tools): free calculators for Corporation Tax, deadlines, late filing penalties and interest, director's loan (s.455) tax, capital allowances, chargeable gains, company size and long accounting periods, plus an iXBRL accounts checker, each with a worked example and GOV.UK sources
- [Developers and AI assistants](https://taxley.co.uk/developers): the same calculators for AI assistants and code, free and with no key: an MCP server at taxley.co.uk/mcp (Streamable HTTP), a JSON API with an [OpenAPI description](https://taxley.co.uk/api/v1/openapi.json), and embeds for websites
- [Corporation Tax glossary](https://taxley.co.uk/corporation-tax-glossary) (CT600, UTR, iXBRL and other terms) and [CT600 boxes explained](https://taxley.co.uk/ct600-boxes) (what goes in each box of the Company Tax Return)
- [What you can file with Taxley](https://taxley.co.uk/uses): CT600 returns and accounts by filing job, company type and for accountants; [dormant company tax return](https://taxley.co.uk/dormant-company-tax-return-software) and [property company tax return](https://taxley.co.uk/property-company-tax-return): filing a nil CT600, and CT600 filing for rental property companies
- [Do I need an accountant?](https://taxley.co.uk/do-i-need-an-accountant): what you can file yourself with Taxley, and which returns it doesn't cover yet
- [FAQ](https://taxley.co.uk/faq) and [About Taxley](https://taxley.co.uk/about)
- [Press & brand](https://taxley.co.uk/press): official descriptions, company facts and logo files

## Guides

- [All guides](https://taxley.co.uk/guides), including [Best CT600 filing software in the UK (2026)](https://taxley.co.uk/guides/best-ct600-filing-software-uk), [How much it costs to file a CT600](https://taxley.co.uk/guides/how-much-does-it-cost-to-file-a-ct600) and [Companies House software-only accounts filing from April 2028](https://taxley.co.uk/guides/companies-house-software-only-accounts-filing-2028)
- [How to file a CT600 yourself (without an accountant)](https://taxley.co.uk/guides/how-to-file-a-ct600-yourself)
- [Free HMRC CT600 filing has closed: what to use now](https://taxley.co.uk/guides/hmrc-filing-service-closed-choose-ct600-software)
- [What is a CT600 and how do you file one?](https://taxley.co.uk/guides/what-is-a-ct600-and-how-to-file)
- [How to file a dormant company tax return](https://taxley.co.uk/guides/dormant-company-tax-return)
- [Corporation Tax rates and marginal relief 2026/27](https://taxley.co.uk/guides/corporation-tax-rates-and-marginal-relief)
- [Corporation Tax deadlines: when to pay and file](https://taxley.co.uk/guides/corporation-tax-deadlines-explained)

## Company

- Legal name: Taxley UK LLP, a limited liability partnership registered in England and Wales
- LLP number: OC461735 ([Companies House record](https://find-and-update.company-information.service.gov.uk/company/OC461735)); its members include Taxley Limited (company no. 17299929)
- Incorporated: 30 September 2026
- ICO registration (data protection): ZC263823 ([ICO register entry](https://ico.org.uk/ESDWebPages/Entry/ZC263823))
- Registered office: 27 Old Gloucester Street, London, WC1N 3AX
- Contact: support@taxley.co.uk or [the contact page](https://taxley.co.uk/contact)