Step by step instructions

First Ensure you have the correct documents

screen shot of ixbrl viewer

HMRC require ixbrl accounts and computations to be attached in most cases. ixbrl is a format which can be read by both humans and computers as the facts in the document have computer readable tags giving context. Some accounts systems can produce this such as VT Final Accounts, or your accountant may be able to provide them.

If you have your own ixbrl skip to the next stage. If you wish you can also use the viewer to see the tags in the files. Log in and go to 'You have ixbrl files', browse to the file on your machine and press upload. You can then use 'View File' to see the content and 'View Tags' to see the tags.

If you do not have your own ixbrl we can convert these manually from your own records. Email the records to to request a conversion. Prices start at £25 for micro entity accounts. You will receive an email saying when the files are complete.

Then Purchase a Use

screen shot of ixbrl viewer

If you have your own IXBRL Go to 'You have returns that can still be submitted', then click the button 'Click Here to buy additional returns'. You can then buy a return with a credit or debit card.

If you have purchased IXBRL from us Go to 'You have ixbrl files in storage'. Here you can review the files. If you are happy with them you can purchase them using the 'To purchase files from us click here' button. You can then make a payment with a debit or credit card to purchase files and returns. You require a return for each submission.

Once you have purchased what you need, go back to the Welcome page, find your new return in the list, and press the Edit Form button next to it.

Upload your accounts and comps.

screen shot of file uploading screen

If you have purchased files from us they may already be attached. You can tell this as they will be in the table at the bottom of the page. If so skip to the next step

If you have iXBRL on your computer you can either use the box in the ‘Select File Here’ row. Then press 'Upload File'. Normal naming rules for computer files apply, please keep below 50 characters, avoid using ‘.’s in the name and keep below 2MB. It is unlikely that an iXBRL file will be this big, and pdf files over the limit can often be reduced by saving with reduced compatibility (ask whoever produced the file to do this).

If we have produced your files or you have viewed them using our viewer they will be in the download box where is says ‘or from store’. Then press 'Upload File'.

The system will know whether an iXBRL file is Accounts or Computations. Otherwise it will assume the file is a pdf. If using a pdf, choose what type it is from the appropriate drop‐down box before you press the Upload Form button.

If an iXBRL set of computations and either a pdf or iXBRL version of the accounts are not to be included, you must include the reason why from one of the reasons in the drop‐down box. This means that the CT600 will be accepted at the gateway, but not that HMRC will accept it after looking at it.

Fill in the form

screen shot of first form page

Uploading computations will update the return accordingly, with company name, dates and various figures. Updating accounts will update company registration and turnover.

However, some parts of the tax return will not have been completed automatically. For instance, whether it is a new or amended return, who is sending it Agent or Company and the capital allowance information. You need to look at all the pages of the return. Pressing example of go right icon moves you through the forms. Do this and fill in anything you need to. Totals (in pink) will be calculated for you.

If you need to refer to the HMRC CT600 guide, press example of open guide icon .

Sign the form

screen shot of last form page

This is the last page. You need to enter your name and position and ‘sign’ the form by ticking the box. When you have filled in this page, you can press this button example of up iconto take you back to the first page

Create the transmission file

screen shot of transmission page, before transmission

Press the ‘Prepare HMRC’ button. With any luck, it will say 'no errors found' in the red block. A printable version of the old paper CT600 will be shown and all of the information in the file is shown in the blue and white table on the right. You can also press the email button example of email icon to get the details in the table sent to you or the print button example of print icon to print it out.

When you are happy, enter your government gateway username and password in the ‘Submit This File Now’ box.

Transmit the file

screen shot of transmission page, after transmission

Assuming your password is correct, you will get a transition screen while the server waits for a response from HMRC. Then you will see this. An email of the CT600 details will be sent to you.

You should wait until the message, good or bad, appears. If you leave before the message, the return will read 'In Transit' and you should go to 'Prepare HMRC' again to get the response.

Hopefully, it will say successful submission, but if it does not you can go back and change things in the return.

After a successful return, the return will move to 'Returns that have already been submitted'. You will be able to press ‘View Details Sent’ and see these details again at any time.

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