iXBRL accounts and tax computation built for your CT600
Taxley builds the iXBRL accounts and the iXBRL tax computation for your CT600 from the figures you enter, checks each file against its taxonomy, and files them to HMRC with the return. It doesn't turn accounts prepared elsewhere, such as a PDF, into iXBRL, and it builds micro-entity and small-company accounts only.
Preparing and previewing is free. You pay one fee per return, only when you choose to file.
Last reviewed
What can't Taxley do with iXBRL accounts?
Taxley builds iXBRL from your figures; it doesn't tag documents made elsewhere. If your accounts were prepared elsewhere in iXBRL, you can upload that file instead, and Taxley still builds the computation.
- Converting accounts. Taxley doesn't turn PDF, Word or spreadsheet accounts into iXBRL. You enter the figures, or import a trial balance, and it builds the accounts from them.
- Other accounts. Accounts for medium-sized or audited companies, and frameworks other than FRS 105 and FRS 102 Section 1A.
- A directors' report. Taxley doesn't prepare one.
- Older periods. Some earlier accounting periods. Before you pay, Taxley checks whether it can file yours.
- Advice. Taxley is software from Taxley UK LLP, not an accountant or tax agent. A file that passes the taxonomy check can still hold wrong figures; the directors stay responsible for them.
Which iXBRL files does Taxley build for a CT600?
Two kinds of iXBRL file go to HMRC with the CT600: the accounts and the tax computation. HMRC needs both in iXBRL, a format that tags each figure so its systems can read it (GOV.UK: XBRL guide for UK businesses).
| File | Tagged with | Where it goes |
|---|---|---|
| Full accounts | The FRC 2025 taxonomy | HMRC, with the CT600 |
| Filleted accounts | The FRC 2025 taxonomy | Companies House |
| Tax computation | HMRC's CT 2025 taxonomy | HMRC, with the CT600 |
A period of account longer than 12 months gets a computation for each of its two accounting periods.
How does Taxley build the iXBRL accounts and computation?
From one set of figures, with nothing to generate by hand.
- Enter the figures. Type them in or import a trial balance as a CSV or Excel file.
- Taxley builds the files. The accounts, the computation and the CT600, built again each time the figures change.
- Taxley checks them. Each file is checked against its taxonomy before it can be filed.
- You review them. Read the accounts and the computation before you pay.
- Pay and file. Taxley sends the CT600 with both files to HMRC, and later files the filleted accounts at Companies House. Once sent, the files are kept as filed.
The free iXBRL accounts checker checks a file made elsewhere.
What does it cost to file iXBRL accounts with Taxley?
The iXBRL files are part of the return: £49.95 with micro-entity accounts or £139 with small-company accounts. There's no separate charge for tagging or for filing the accounts at Companies House. Every plan is on the pricing page.
Frequently asked questions
Do I need separate iXBRL tagging software?
No. Taxley tags the accounts and the computation as it builds them, from the figures you enter, so there is nothing to tag or convert yourself. You see both before you pay.
Which taxonomies does Taxley use?
The accounts use the Financial Reporting Council's 2025 taxonomy, and the tax computation uses HMRC's CT 2025 computational taxonomy. Taxley checks each file against its taxonomy before it is filed.
What happens to the iXBRL files if I change a figure?
Taxley builds them again from the new figures, so the files you check are the ones that will be filed. Once the return has gone to HMRC, the files are kept exactly as filed.
Can I check an iXBRL file made elsewhere?
Yes. The free iXBRL accounts checker checks a file against the taxonomy. If your accounts were prepared elsewhere in iXBRL, you can upload them in place of Taxley's, and Taxley checks them against the return.
Can I download the accounts and computation?
Yes. You can download PDF copies of the CT600, the accounts and the computation, marked as drafts until the return is filed, and view the iXBRL files themselves on the filing page.
Ready to see your iXBRL files?
Enter the figures, check the accounts and computation Taxley builds, and pay only when you file.