CbC XML Schema – User Guide (Version 2.1)

Summary

This is the DITC's technical User Guide (Version 2.1, issued 8 December 2025) explaining how to complete the OECD CbC XML Schema v2.0 for Country-by-Country (CbC) Reports filed with the Cayman Islands Tax Information Authority via the DITC Portal. It supplements, but does not replace, the OECD's official CbCR XML Schema User Guide, and sets out Cayman Islands-specific values and formatting rules for key XML data elements (e.g. country codes, TINs, message and document reference IDs).

The guide applies to Reporting Entities of Multi-National Enterprise (MNE) Groups that are resident in the Cayman Islands and are required to file CbC Reports, as well as to the Constituent Entities of such groups whose data must be included in those reports.

• Country code: Use 'KY' as the transmitting/receiving country code.
• TIN: Use the General Registry (GR) number as the TIN for Cayman Islands-resident entities.
• Reference IDs: Follow specific formats for MessageRefID, DocRefID and CorrDocRefID.
• Prohibited characters: Avoid prohibited XML characters.
• Validation elements: Ensure all 'validation' elements are present so files are not rejected.
• Corrections and deletions: Structure corrections and deletions to previously filed CbC Reports using DocTypeIndic, CorrDocRefID, and unique DocRefIDs.

The Authority will reject submissions containing validation errors, prohibited characters, or incorrectly formatted identifiers until corrected and resubmitted. As a guidance document, it does not itself create new legal reporting obligations beyond those in the CbCR Regulations, but it is essential reading for anyone preparing a technically valid CbC XML submission.

Key obligations

• The Reporting Entity's Primary Contact must obtain DITC Portal login credentials by completing the notification procedure described in the DITC Portal User Guide before filing a CbC Report.
• CbC Reports to the Authority must be prepared and filed using the OECD's CbC XML Schema v2.0, downloaded from the OECD website.
• The Reporting Entity must be resident in the Cayman Islands to submit a CbC Report via the DITC Portal.
• TransmittingCountry and ReceivingCountry elements must equal 'KY' for all filings to the Authority.
• SendingEntityIN must match the alphanumeric eleven-character CbCR ID issued to the Reporting Entity upon DITC Portal registration.
• MessageRefID and DocRefID (and, for corrections, CorrDocRefID) must be constructed in the required format (country code + reporting year + CBC ID + unique identifier) and must be unique.
• ReportingPeriod must be entered in YYYY-MM-DD format and must match the fiscal year end recorded during DITC Portal registration.
• The TIN for Cayman Islands-resident Constituent/Reporting Entities must be reported as the General Registry (GR) number with the correct entity-type prefix (CR, LC, PX, LP or TR); 'NOTIN' may only be used where no TIN exists or the entity is an unregistered trust.
• All XML submissions must avoid prohibited characters (e.g. &, ', <, >, ", &#, --, /*) and use the correct XML entity equivalents where applicable.
• All 'Validation' elements must be present in every data record; filers should perform a technical check before submission and correct any missing elements.
• Where a validation error is identified by the Authority, the filer must review the error notification, correct the XML data and resubmit until all validation errors are resolved.
• Corrections or deletions of previously submitted CbC Reports must use a new unique DocRefID and correctly reference the prior DocRefID via CorrDocRefID, following the same formatting rules as new filings.

Applies to

Multi-National Enterprise (MNE) Groups, Reporting Entities, Constituent Entities resident in the Cayman Islands