Last updated: 18 Oct 2025
United Kingdom — Reporting mechanisms (FATCA & CRS/AEOI)
How UK financial institutions report FATCA and CRS/AEOI data: responsibilities, technical reporting channels, data content, annual cycles, error corrections, data quality, governance – and the interface with the QI regime.
At a glance
- Competent authority: HM Revenue & Customs (HMRC) as national hub.
- FATCA model: Model 1 IGA (report to HMRC, onward transmission to IRS).
- Channel: Electronic submission via HMRC online services/interfaces (XML-based, secure transport).
- Scope: Account holder/account data, tax identifiers (US TIN, where required), balances, income, gross proceeds.
- Rhythm: annual reporting (deadlines published by HMRC in AEOI guidance).
Who is affected?
- Banks, investment firms, custodians, funds/asset managers (depending on status).
- Insurance undertakings (relevant cash value/insurance products).
- Other reporting financial institutions as defined under FATCA/CRS.
1) Roles & responsibilities
- HMRC: receipt, validation and onward transmission of FATCA data to the IRS; AEOI/CRS exchange with partner jurisdictions.
- Institution: collection/validation of client master data (KYC/tax), indicia checks, TIN capture, reporting and corrections.
- FCA/PRA (supervisory): oversight of governance, AML/KYC and systems & controls; indirect relevance for data quality and reporting governance.
2) Reporting channels & technology
| Path | Description | Notes |
|---|---|---|
| HMRC online services / AEOI portal | Electronic submission of structured XML files (FATCA & CRS) via HMRC’s online system using appropriate credentials/authentication. | Validation against schema; retrieve and process acknowledgements and error messages. |
| Registration | IRS FATCA registration (GIIN) plus registration with HMRC’s AEOI service for data transfer and reporting obligations. | GIIN must be included where applicable; lack of a valid GIIN can trigger 30% US withholding on certain payments. |
| Formats | FATCA/CRS XML aligned with the OECD/HMRC schema; transport and encryption requirements as per HMRC technical specifications. | Monitor schema versions/changes; perform test transmissions before first live filing or after major system changes. |
3) Reported data (content)
- Identifiers: account holder (individual/entity), addresses, tax residency, US TIN (where reportable), and, where relevant, GIIN of intermediaries.
- Account information: account numbers/IBANs, account type, year-end balance or value.
- Income/proceeds: interest, dividends, gross proceeds/disposals; for insurance, relevant payments under in-scope contracts.
- Due diligence status: documentation status (W-8/W-9/CRS self-cert), indicia review, and, where relevant, undocumented/recalcitrant status.
4) Rhythm & timelines
Reporting is annual. Specific filing deadlines are published by HMRC in its AEOI/FATCA guidance. A proven internal sequence is: cut-off extraction → technical validation → management sign-off → submission → monitoring of error reports.
5) Data quality & error correction
- Error messages (business/schema): After submission, HMRC provides feedback (for example TIN issues, country codes, amount fields).
- Corrections: Amendments or replacement files in line with HMRC specifications; maintain consistent record keys for traceability.
- TIN management: Process for missing/invalid US TINs (monitoring, client outreach, reasonable explanations, data remediation).
- GIIN checks: Regular reconciliation against the IRS FATCA FFI list, documented as part of internal controls.
6) Governance & controls
Key controls
- Designated reporting owner role plus deputy
- Four-eyes principle / management sign-off
- Change/release process for schema and system updates
- Audit trail (input sourcing, mapping, validation, submission, corrections)
- Training (front/KYC, tax operations, IT/data)
Policies & interfaces
- FATCA/CRS policy (including TIN escalation, indicia workflows, documentation rules)
- Data protection/information security (legal basis, retention periods)
- Interface to QI: consistent W-8/W-9 data, “reason to know”, alignment of IRC Chapters 3/4 with IGA due-diligence and AEOI reporting.
FAQ
Who is the reporting authority in the UK?
HMRC acts as the central reporting authority for FATCA (with onward transmission to the IRS) and for CRS/AEOI exchanges with partner jurisdictions.
Do UK institutions report directly to the IRS?
No. Under the Model-1 IGA, FATCA reports are filed with HMRC, which then forwards the data to the IRS. IRS registration (GIIN) is still required.
What data is reported?
Identifiers (including US TIN, where required), account numbers, year-end balances/values and relevant income/gross proceeds in line with the schema.
How does a correction work?
Following an error message, identify the record, correct it both functionally and technically and resubmit it as an amended or replacement file – in line with HMRC’s specifications.