New Transmission Procedures for U1.1 Reporting (CSSF)
CSSF
The previous submission methods remain available during a transition period until 28 February 2025. A detailed user guide has also been published to help entities adapt.
In addition, the updated Guidelines on U1.1 reporting (version 6.1, February 2025) now include technical specifications for XML format and explanations of the new submission channels (eDesk & API).
Key points at a glance
Who is concerned?
UCIs, SIFs, SICARs under CSSF supervision
Frequency & deadline
Monthly, due by the 10th calendar day of the following month
Submission methods
XML via eDesk or API (S3 protocol)
Transition period
Old channels accepted until 28 Feb 2025
Legal framework
CSSF Circular 15/627 (amended by 25/871), Guidelines v6.1
Why it matters
These changes aim to:
modernize and secure the reporting process,
harmonize formats to reduce manual errors,
improve the reliability and efficiency of regulatory reporting.
The new framework becomes mandatory from March 2025 onward.