From 1 April 2011 onwards, all companies and organisations must submit their Company Tax Return online for any accounting period ending after 31 March 2010.
From the same date, companies and organisations must pay any Corporation Tax and related payments due electronically (for example by Direct Debit).
The rules on how you calculate the Corporation Tax you need to pay, or how to fill in the return itself, have not changed. Only the format of what you send and how you send it to HMRC has changed.
This guide explains who is affected and when and what action you must take to ensure your return is submitted in the correct format. It also tells you where you can get more information and advice.
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From 1 April 2011, all companies and organisations must submit their Company Tax Return online for any accounting period ending after 31 March 2010.
Additionally, if you have to prepare accounts under the Companies Act 2006, you must submit your accounts and computations in a set format - Inline eXtensible Business Reporting Language (iXBRL). iXBRL is an IT standard designed specifically for business financial reporting - not just tax filing. But don't worry, you don't have to be an IT expert to file online, your software will do most of the work for you.
If your company or organisation has to prepare accounts under the legislation governing certain financial institutions - such as building societies, friendly societies and industrial and provident societies - you must also submit accounts and computations in iXBRL format.
More about submitting accounts in iXBRL or PDF format (PDF 33K)
You must tag the data in your company accounts that relates to the period of your Company Tax Return. Comparative data for the preceding period should also be tagged. However, tagging data for the preceding period in the first year of mandatory online filing is not required.
Please note: The accounts template within HMRC's free software is not suitable for accounts prepared by charities. Until HMRC provides a template that is suitable, smaller charities can choose to send their accounts to HMRC in iXBRL format (using commercial software) or as a PDF. Follow the link below to find out more about what HMRC means by 'smaller charities' and what format is acceptable for their accounts.
If you run an unincorporated organisation such as a charity, club or society, or a smaller charity which is incorporated under the Charities Act, you must submit your computations in iXBRL format. You can choose to submit your accounts in either iXBRL format or as a PDF.
Company Tax Returns for smaller charities: filing online - format for accounts
You can only include one iXBRL statutory accounts file as part of your online Company Tax Return. If iXBRL accounts are being included as part of the online return, any additional accounts forming part of the return must be attached as PDF files.
If you have any other information that you need to include as part of your Company Tax Return - for example, claims or elections, reports or statements - you can attach these to your online return as a PDF.
The maximum size for combined attachments when using the free HMRC software is 5MB.
If you're already using or intend to use commercial software to make attachments, please check with your supplier that the product is compatible with the Corporation Tax online service.
More about how to file your Company Tax Return online
Any overseas company that's resident in the UK must submit its Company Tax Return online and attach accounts and computations in iXBRL format.
If your company is not considered to be resident in the UK but is still carrying out a trade here through a permanent establishment, or through a branch or agency, you must submit the accounts and computations relating to your company's UK activities in iXBRL format.
More on overseas companies and Corporation Tax
Companies that are part of a group must submit their individual company accounts in iXBRL format.
If a parent company chooses - or is required - to prepare group accounts as well as individual accounts, it may instead deliver consolidated accounts in iXBRL format. But the consolidated accounts must contain the same information about the parent company as its individual accounts would have done.
A parent company that doesn't prepare consolidated accounts must provide its individual accounts in iXBRL format and any group accounts as a PDF.
From 1 April 2011 you must make all Corporation Tax and related payments electronically. Related payments include interest charged on overdue Corporation Tax and penalties for not filing your Company Tax Return on time.
You can pay electronically online using:
You can also pay electronically but not online using:
Read more about paying Corporation Tax
In very limited circumstances you may not have to submit an online Company Tax Return and HMRC may accept a paper return instead. These include:
These circumstances are more fully described in the legislation which authorises and regulates this new HMRC requirement. If after reading the legislation you believe your company or organisation should be exempt from online filing, please write to your Corporation Tax Office and provide full details of the reason why. HMRC will review this and advise you whether or not the exemption applies.
Read the legislation for Corporation Tax online filing
Most companies and organisations, or their agents, already use commercial software to prepare accounts, computations and submit Company Tax Returns. But it's important that you check with your provider that the software you're using allows you to submit your return online in the right format. Follow the link below to view a list of commercial software that has been tested for compatibility with HMRC's online systems.
Corporation Tax commercial software options
Companies or organisations with straightforward tax affairs can use HMRC's free online filing software to submit their return. HMRC's software can only be used to submit returns for accounting periods starting on or after 1 April 2008. The software includes online templates for your accounts and computations information. If you use these templates, your accounts and computations will be attached to your online return form and submitted to HMRC in the right format. The accounts template also includes a joint filing option. You can choose to enter your accounts data once and then submit that information to HMRC (as part of your Company Tax Return), and to Companies House using a 'one stop' online facility.
If you use an integrated software package or stand-alone accounts software, your software will automatically insert the majority of the necessary iXBRL tags and produce an iXBRL accounts file. If you enter data into freeform boxes that don't have a pre-defined description and iXBRL tag, most software includes functionality to help you identify and add the correct iXBRL tag yourself.
If you currently use an IT application such as Word or Excel to prepare your accounts and/or computations, you should think about how you're going to submit them to HMRC, in the right format. You may choose to use commercially available software, ask an agent to submit your return for you, or use HMRC's free software if that is suitable. Another option is to purchase software that will convert Word documents or Excel spreadsheets into iXBRL format. This will allow you to attach accounts and computations to your online return form in the correct format but, for this option, you'll need to understand accounting principles and have some knowledge of how XBRL works.
HMRC does not expect you to have to change software suppliers in order to submit your Company Tax Return on time. If the delivery date of particular iXBRL-enabled software prevents you from submitting your return on time, HMRC will consider this sympathetically. Follow the link below to find information about managing the transition to filing online and using iXBRL.
If you run a large company with more complex tax affairs, you may already have - or you may be planning to use - specially developed software to meet your company's needs.
But no matter what software or online filing method you choose, you must ensure it's capable of submitting your company's accounts and computations to HMRC in the required format.
Setting up your Corporation Tax online account
Who can use HMRC's Corporation Tax online filing software
Read more about the Companies House and HMRC joint filing service
Appointing someone to deal with your Corporation Tax affairs
Managing the transition to filing online and using iXBRL
It's a good idea to plan how you are going to submit online Company Tax Returns and pay Corporation Tax electronically, well before your paying and filing deadlines.
To make the transition to online filing as smooth as possible you should:
Find out about the different ways to pay Corporation Tax electronically
Appointing someone to deal with your Corporation Tax affairs
Corporation Tax Online: setting up and managing your online account
HMRC has published guidance to help you set up your Corporation Tax Online account and submit your return online.
There is also an online demonstrator that takes you through the various screens involved in registering and enrolling for Corporation Tax Online, submitting a return and using the online service.
Follow the links below to find this help and support.
Corporation Tax Online: setting up and managing your online account
Help to file your Company Tax Return online
Corporation Tax online demonstrator
Find detailed guidance on online filing and electronic payment
