Seahorse Fact Sheet


Seahorse® fact sheet

What is Seahorse?

Seahorse is CoreFiling’s secure on-demand service, which provides intelligent iXBRL tagging of company accounts that have been produced using either Microsoft Word or Excel. Seahorse is also available under the ‘OpeniXBRL’ brand from IRIS.

Since Seahorse isn’t a client-side application, how does it work?

Provided over the internet as a secure on-demand service, Seahorse is accessed via a standard web browser interface, with no additional software to install or maintain. Using the site, secured by strong encryption, is similar to using online banking.

Do I have to understand XBRL in order to use Seahorse?

No. Seahorse’s automatic tagging capability and intuitive interface means that accounts can quickly and easily be converted to iXBRL format without the need for any XBRL knowledge on the part of the user.

Will I need to change the way I produce my accounts?

No. Tight integration with Microsoft Word and Excel means that you can continue to produce your company accounts in exactly the same way as before.

Who can use Seahorse?

Seahorse is for accountancy practices and accountants in business who need to prepare their accounts in iXBRL. It is applicable to all filers who need to submit iXBRL accounts.

HMRC filers must submit their tagged accounts together with the CT600 form and tax computations via the Government Gateway.

Revenue Ireland filers will benefit from Seahorse’s simple approach to tagging when submitting documents via the Revenue’s Online Service (ROS) as required by the Revenue mandate.

No iXBRL expertise is required as Seahorse intelligently tags Microsoft Word or Excel documents and provides an intuitive review process for peace of mind.

Can I submit my iXBRL accounts directly to Companies House?

Once Seahorse has converted your UK GAAP accounts to iXBRL, you can take advantage of the option to file the iXBRL document directly with Companies House from within the product.

How long does it take to tag a document?

Once users are comfortable with Seahorse, producing iXBRL documents is much faster than using other conversion techniques.

How does Seahorse accelerate tagging in subsequent years?

Once you have used Seahorse to create your iXBRL accounts, the tagging process in subsequent years couldn’t be easier. Seahorse gives the opportunity to re-apply the tagging decisions you made the previous year to form the basis of a new document containing the recently prepared accounts. Line items that appear in both years will be tagged this way, and any remaining items will be auto-tagged as usual. Both the existing items and newly auto-tagged items can then be reviewed in the normal way, either together or separately. As the existing items should already be correctly tagged from the previous year, very few changes should be required. The whole process saves considerable time and effort.

Why is Seahorse better than outsourcing to a third party?

As you are in control of the tagging and not relying on an outsourced partner to do it for you, there are no capacity issues and no surcharges during peak times. However, if you do choose an outsourced solution, you can always check the quality of the documents produced using CoreFiling’s Magnify document review tool.

Why is Seahorse better than ‘drag and drop’ tagging tools?

Seahorse has been proven to take less than half the time of ‘drag and drop’ alternatives, because it automatically tags the Word or Excel document. The risk of mis-tagging is significantly reduced as the cloud-based learning engine behind Seahorse remembers previous tagging actions in order to make continually smarter tagging decisions. Sophisticated proprietary algorithms make this possible, combined with the collective experience of all the professionals who have used it to tag their accounts.

Why is an internet-based solution preferable to a desktop tool?

There is no software to buy, install and maintain on your local systems and you will always have access to the latest version of the software. There are no capacity issues, as cloud technology will automatically scale to accommodate peaks and troughs in demand for the application. Security is extremely strong – Seahorse has passed the security requirements of a number of the very largest accounting practices in the UK. The security arrangements are similar to those found in online banking systems.

Why do I buy from partners and not directly from CoreFiling?

CoreFiling devised and pioneered he standardisation of the iXBRL format and developed the Seahorse conversion software. Our focus remains on continually developing and enhancing this software. For example CoreFiling retains responsibility for incorporating updates to UK GAAP, Irish GAAP, IFRS and other relevant taxonomies, as well as working with regulatory bodies worldwide to promote iXBRL as a business reporting standard. In order to help you to meet the HMRC and Revenue Ireland mandates we have selected a number of reseller and service provider partners who are uniquely placed to provide dedicated sales and expert service to assist you. Details of our partner relationships can be found below.

Where can I find out more?

Seahorse is available only from recognised CoreFiling resellers and service providers. If you have a specific query with which we can help you please email Otherwise, please contact one of our partners listed below. Find out more about our partners here.


For corporates Alui 01420 550750 Email
BDO 0118 925 8505 Email
For accountancy practices IRIS 0844 815 5555 Email