Filing of Structured Annual Financial Reports

This page and the NSM help and FAQs publication have been updated, including tips on how to address common filing issues.

About Structured Reporting

As part of the European Single Electronic Format (ESEF) initiative, there is a standard for digital financial reporting by companies with transferable securities admitted to trading on UK regulated markets. 

Filing Annual Financial Reports (AFRs) with the FCA for in-scope issuers on this basis is mandatory for financial years starting on or after January 2021, but we have encouraged issuers to file on a voluntary basis beforehand to improve transparency and to help themselves prepare. 

To determine whether the requirements apply to you, please review the rules in DTR 4 and the TD ESEF regulation. More information on the ESEF initiative can be found here

Issuers and the public can use the National Storage Mechanism (NSM) to view and download structured AFRs. The NSM user guide provides instructions. 

The Structured Filing Process

Step 1: registration and authorisation

If submitters have not previously used ESS, they will need to register. Submitters will also need to be authorised by the issuers they want to submit on behalf of. We recommend you register and seek authorisation ahead of submission to avoid delay. Our NSM submitter user guide provides information about this process.   

Step 2: producing your structured AFR  

Before attempting to submit, it is essential that submitters are familiar with the process and requirements for preparing a structured report. This is a complex area and you may need to seek support from specialist advisers or software providers. The documents you must review include: 

  • The TD ESEF regulation, which specifies the tagging rules and the permitted taxonomies. 
  • Depending on whether you are submitting a tagged or untagged report and which taxonomy you use, the ESEF and/or UKSEF filing manuals, which set out technical guidelines for preparing structured reports. 
  • The XBRL guidelines on taxonomy and report packaging, which prescribe how taxonomy and report packages must be structured. 
  • The FCA technical guidelines, which include information on FCA-specific requirements for submission format and naming.  
  • The NSM submitter user guide, which provides a step-by-step guide for submitters to uploading information to the NSM. The guide includes information on how to submit a tagged report for validation only (test submissions), how to view any warnings/errors and how to raise a support ticket. 
  • The NSM help and FAQs publication, which provides guidance for some frequent issues, including how to resolve common validation errors. 

Step 3: submitting your structured AFRs  

Structured AFRs must be submitted on ESS using the dedicated case category (‘Annual Financial Reports in Structured Electronic format (ESEF)’). The ‘National Storage Mechanism’ case category should continue to be used for unstructured (*.pdf) filings of AFRs.  

AFRs tagged according to a taxonomy must be uploaded in a *.zip package format. AFRs not tagged according to a taxonomy must be submitted as a *.html or *.xhtml file. Our NSM submitter user guide provides information on how to submit.

Step 4: checks and validation  

It is crucial that structured submissions are of sufficient and appropriate quality. The Financial Reporting Council’s (FRC) Lab has undertaken a review of tagged filings and has identified some areas where quality is not of the expected standard. The Lab’s report provides details of key issues that issuers might want to consider. More information on the importance of quality submissions can be found in a joint FCA and FRC letter.   

Files submitted to the NSM will be subject to checks against the filing guidelines and, where tagging is used, the taxonomy rules. If there are any errors generated, files will be rejected and will not be published on the NSM. Where a rejection occurs, the submitter will be notified and will need to resubmit using a new case. To resolve these issues, a submitter may need to review the guides (see step 2), approach taxonomy-issuing bodies and seek support from specialist advisers or software providers. Warnings do not prevent a report from being published but need to be investigated. If you have investigated a warning and concluded there is no underlying issue to address, no further action is required.  

We publish successful submissions on the NSM. See the NSM user guide for instructions on how to view and download structured AFRs on the NSM.  

If you have any questions

Relevant information can be found in the links provided on this page.  Submitters must review these and seek specialist advice where necessary. For issues related to the FCA’s submission process that are not covered in the published information, please raise a support request in ESS. If you do not have access to ESS, please email [email protected].

Page updates

09/05/2022: Information added Page and FAQs updated to address common filing issues
22/11/2021: Information added
04/10/2021: Information changed Page updated to reflect move from ESEF optional to mandatory