SOLV Reporting in Luxembourg: The CSSF’s COREP Own Funds Return

ByRegReportingDesk
RegReportingDesk card: CSSF, Commission de Surveillance du Secteur Financier, Luxembourg

SOLV reporting is the CSSF’s own funds return for Luxembourg banks. The CSSF handbook “Reporting requirements for credit institutions” (version 8.3 of 17 November 2025) splits it into two domains: SSOLV, own funds requirements (solvency ratio) on an individual basis, and CSOLV, the same information on a consolidated basis. Both rest on Article 430(1)(a) of Regulation (EU) No 575/2013 (the CRR) and on Commission Implementing Regulation (EU) 2024/3117. The CSSF handbook lists C 01.00 to C 05.00, C 07.00 to C 14.00, C 16.00 to C 25.00 and C 32.00 to C 35.00 within SSOLV and CSOLV, subject to the template-specific frequencies and conditions; C 06.00 is additionally listed for CSOLV. Quarterly reporting is remitted on 12 May, 11 August, 11 November and 11 February.

Since the March 2025 reference date these files reach the CSSF through eDesk or its S3 interface under the file subtype COREPX. The acceptance logic is strict. A file that raises only warnings stays NOT-ACCEPTED until each warning is explained in eDesk and the CSSF accepts the explanations. The CSSF’s reminder sequence, which ends with a notice to the bank’s authorised managers, starts the day after the remittance date.

Much of what decides acceptance sits around the figures. The CSSF’s formal verification rules reject a file for a non-compliant name, an unexpected accounting version or an entry point that does not match the reference period, and those technical checks run before any validation rule touches C 01.00 or C 03.00.

Related reading: COREP Reporting Explained

The legal basis of SOLV reporting: Article 430(1)(a) CRR, Implementing Regulation 2024/3117 and the CSSF domain codes

The obligation itself is European. Article 430(1)(a) CRR requires institutions to report on own funds requirements, and the CSSF handbook cites that point as the legal basis of both SSOLV and CSOLV (it cites the same point for the leverage ratio module, which is a separate domain). The formats, frequencies and dates come from Implementing Regulation (EU) 2024/3117 of 29 November 2024, published in the Official Journal on 27 December 2024. For SSOLV the handbook points to Articles 5, 6 and 8 of that Regulation; for CSOLV to Articles 7 and 8.

  • Article 5: own funds and own funds requirements on an individual basis, quarterly reporting.
  • Article 6: the same on an individual basis, semi-annual reporting, including securitisation, sovereign exposures and material operational risk losses.
  • Article 7: own funds and own funds requirements on a consolidated basis, with the group solvency information on a semi-annual frequency.
  • Article 8: additional templates for institutions that must disclose certain IRB and counterparty credit risk information under Part Eight CRR.

Implementing Regulation 2024/3117 replaced Implementing Regulation (EU) 2021/451, which ceased to apply from 1 January 2025 except for its market risk provisions (Article 25, as amended). Like its predecessor it is directly applicable, so Luxembourg has no transposing text for the templates. The national layer is procedural. Circular CSSF 14/593, last amended by Circular CSSF 22/823 in December 2022, requires transmission in line with the ITS, the EBA data point model and validation rules, chapter 5 of the handbook and the CSSF’s plausibility checks. It places responsibility for deadlines, accuracy and completeness on the bank’s management and requires the files sent to the CSSF to be kept for at least five years. Its text still names Implementing Regulation 2021/451 as the ITS Regulation; the handbook carries the current 2024/3117 references.

The name needs one clarification. The handbook only ever uses prefixed forms: the domains are SSOLV and CSOLV, the eDesk report name is COREP_OF, and the file subtype is COREPX. Template C 15.00 on losses from lending collateralised by immovable property sits in its own domains (SIPLO and CIPLO) under the report name COREP_C15 with the annual subtype COREPY, which the user guide describes as the yearly COREP_OF submission.

Who must report SOLV: the solo, consolidated and branch perimeters

The handbook organises SOLV by entity type, and the entity type decides the accounting version code the file must carry. That code is checked mechanically: rejection rule RULE008 in the CSSF user guide for XBRL reports fires when “the accounting version is not the one expected”.

  • Luxembourg-law credit institutions with foreign branches file SSOLV in accounting version N, the head office and its foreign branches combined after eliminating reciprocal transactions.
  • Luxembourg-law credit institutions without branches file SSOLV in accounting version L.
  • Luxembourg branches of credit institutions whose head office is outside the EU file SSOLV in accounting version L.
  • Credit institutions subject to supervision on a (sub-)consolidated basis also file CSOLV in accounting version C, on the CRR prudential perimeter. Where that perimeter differs from the one in the law of 5 April 1993 on the financial sector, the handbook says the CRR scope prevails.

Two contrasts catch teams that run FINREP and COREP on one set of assumptions. For a Luxembourg bank with foreign branches, the handbook asks for FINREP on an individual basis in versions L, S and N, one for the Luxembourg head office alone, one per foreign branch and one for the whole. The SSOLV table for the same bank asks for version N only. Branches of EU credit institutions are the second contrast: their table in the handbook lists financial information (SFINRP), the B 2.5 tables, the immovable property losses template and table B 4.6, and no SSOLV at all. A Luxembourg branch of an EU bank does not produce SOLV.

Identifiers follow the same split. In the XBRL instance an L or N file identifies the entity as its LEI with the suffix .IND, a consolidated C file uses .CON, and a branch may use its MFI code instead of an LEI.

SOLV has no entry threshold of its own; the thresholds in the Regulation decide which templates inside the module are due (see the caveats below). Articles 9 and 10 of the Regulation also cover certain investment firms, but the CSSF documents used here are written for credit institutions.

One decision is easy to over-read. From the Q1 2025 reference date the CSSF abolished systematic liquidity reporting at sub-consolidated level for subsidiaries of EU groups, outside liquidity sub-groups. The handbook names ALMM, LCRDA and NSFR as the modules concerned. CSOLV is not in that list.

What the report contains: the COREP templates and the CSSF’s reading of C 03.00, C 09.04 and C 33.00

The SSOLV and CSOLV tables in the handbook list the templates and their frequencies as follows.

  • Quarterly: C 01.00 to C 05.00, C 07.00, C 09.00, C 10.00, C 11.00, C 12.00, C 13.00, C 16.00, C 18.00 to C 24.00, C 25.00, C 32.00 and C 35.00.
  • Semi-annual: C 14.00, C 17.00 and C 33.00, plus C 06.00 on the consolidated return only.
  • Mixed quarterly, semi-annual and annual: C 08.00 and C 34.00.

C 01.00 to C 05.00 carry own funds and own funds requirements, with the total risk exposure amount in C 02.00 row 0010 and the capital ratios in C 03.00. Credit risk sits in C 07.00 for the standardised approach and in the C 08 series for IRB, the geographical breakdown in C 09.01 and C 09.02, and the countercyclical buffer inputs in C 09.04. C 14.00 and C 14.01 cover securitisation, the C 16 series operational risk own funds requirements, C 17.01 and C 17.02 material operational risk losses, C 18.00 to C 24.00 market risk, the C 32 series prudent valuation, C 33.00 general government exposures by country, the C 34 series counterparty credit risk and the C 35 series loss coverage for non-performing exposures. The group solvency templates C 06.01 and C 06.02 appear only in CSOLV.

Units follow the handbook’s instance rules. Monetary amounts are reported in the capital currency of the reporting entity, except where a data point carries the CCA dimension value “expressed in currency of denomination”, in which case the amount stays in its own currency. Article 23(1)(b) of Implementing Regulation 2024/3117 sets minimum precisions: monetary data points at a precision equivalent to ten thousands of units, percentages expressed per unit with at least four decimals, integers without decimals. The handbook’s change log records the deletion of its old paragraph on the precision of percentages and numeric data, which leaves Article 23 as the operative rule. For sign conventions the CSSF documents add nothing to the EBA instructions in the annexes to the Regulation. The CSSF requires own funds to be determined under IFRS as adopted in the EU, citing Article 24(2) CRR.

C 03.00: the Pillar 2 rows

The CSSF’s additional guidance spends most of its COREP pages on the memorandum items of C 03.00 (capital ratios and capital levels). Following Article 104a(4) of the Capital Requirements Directive, at least three quarters of the Pillar 2 requirement (P2R) must be met with Tier 1 and at least three quarters of that Tier 1 with CET1, unless the competent authority requires a higher share. The CSSF turns this into three formulas: row 0130 equals 0.08 plus P2R, row 0140 equals 0.045 plus P2R times 0.5625, and row 0150 equals 0.06 plus P2R times 0.75.

Its worked example uses a bank notified of a 2% CET1 P2R. Row 0130 (total SREP capital requirement) is 10%, row 0140 is 5.63% and row 0150 is 7.50%. With a 2.5% capital conservation buffer and a 0.05% institution-specific countercyclical buffer, row 0160 (overall capital requirement) is 12.55%, and adding a 1% Pillar 2 guidance gives 13.55% in row 0190. A bank with no P2R reports only the 8% minimum in row 0130. The CSSF adds that rows 0760, 0780 and 0800 of the combined buffer block in C 04.00 are currently not applicable to Luxembourg credit institutions. Its example is framed around EBA taxonomy 2.8 and version 17 still carries it, so the row numbers are worth checking against the table layout of the framework the file is built on.

C 09.04: the countercyclical buffer rate

C 09.04 carries the inputs for the institution-specific countercyclical buffer rate under Article 140 CRD and CSSF Regulation No 15-01. Each country sheet reports the relevant credit, market and securitisation exposures and their own funds requirements. The weight in row 0110 is the country’s share of total own funds requirements for relevant credit exposures, and the institution-specific rate in row 0140 is the weighted average of the country rates. The CSSF’s placement rules are narrow: row 0130 is filled only where Luxembourg applies a rate for a country that differs from the rate set by that country’s designated authority in row 0120, both rows stay empty on the total sheet, and row 0140 appears only on the total sheet. The CSSF also records that reporting entities sometimes use the wrong country rates, and directs them to the ESRB and BIS rate lists with their application dates. The current Luxembourg setting is tracked in our note on the Luxembourg countercyclical capital buffer.

C 33.00: what counts as general government

For C 33.00 the CSSF excludes exposures to central banks, citing EBA Q&A 2021_5825, and exposures to the multilateral development banks listed in Article 117 CRR. Its basic rules: columns 0010, 0020 and 0290 (and where relevant 0300) are never empty when the bank has something to report, every exposure is classified by accounting portfolio, the residual maturity breakdown in rows 0170 to 0230 is always completed, and the total must equal the sum of the country figures. The CSSF expects the figures to be comparable with large exposures reporting and with the BCL S 2.5 quarterly statistical balance sheet. Its guidance still cites the 1% general government threshold under the old ITS numbering. In Implementing Regulation 2024/3117 that threshold, and the 90% domestic test that triggers the full country breakdown, sit in Article 6(3).

SOLV deadlines: fixed reference dates, remittance dates and first application

The calendar is fixed by Articles 2 and 3 of Implementing Regulation 2024/3117 and repeated in the handbook’s SSOLV and CSOLV tables.

  • Quarterly templates: reference dates 31 March, 30 June, 30 September and 31 December; remittance by close of business on 12 May, 11 August, 11 November and 11 February.
  • Semi-annual templates: reference dates 30 June and 31 December; remittance on 11 August and 11 February.
  • Annual templates: reference date 31 December; remittance on 11 February.
  • If the remittance day is a Luxembourg public holiday, a Saturday or a Sunday, the data are due on the following working day (Article 3(2)).

The quarter now closing is therefore due on the next date in that list, and a 31 December reference date brings the quarterly, semi-annual and annual SOLV templates together on 11 February.

First application dates differ by template. The handbook gives 1 January 2014 for the SOLV domains and 30 June 2021 for C 34.00 and C 35.00. The current Regulation’s first reference date was 31 March 2025, and Article 24(1) deferred the remittance for that date to 30 June 2025 at the latest. On the channel side, the CSSF user guide opened eDesk and S3 for initial quarterly COREP versions from the 2025-03 reference period (from 1 April 2025) and for the yearly COREP OF submission from the 2025-12 reference period (from 1 January 2026).

The preliminary and final version codes follow their own logic. The handbook’s final version “D” marks audited year-end figures and is mandatory for the financial information returns (SFINRP and CFINRP), except for branches of EU credit institutions. The SSOLV and CSOLV tables ask only for the preliminary version, so a SOLV file carries report version N. Revisions still have an EU deadline: Article 3(4) allows unaudited figures but requires revised audited figures “without undue delay” where they deviate, and Article 3(5) applies the same standard to any other correction.

Late or erroneous files follow the reminder sequence in the user guide. Reminder 1 goes out the day after the remittance deadline where the report is missing or erroneous, which the guide defines to include errors and warnings left unexplained or wrongly explained. It reaches the users holding the Bank Prudential Reporting Responsible role and the Responsible level 1 contacts. If no accepted report has arrived two days later, Reminder 2 adds the Responsible level 2 contacts, who must be authorised managers within the meaning of Circular CSSF 12/552.

Submission of SOLV files: eDesk, S3, COREPX file names and XBRL-CSV

Two channels carry SOLV files: an online upload in the eDesk procedure after LuxTrust authentication, or a structured file placed in the “submission” folder of the entity’s S3 bucket for EBA ITS standard reports, with feedback returned as JSON in the “feedback” folder. An eDesk enrolment is needed either way. The user guide assigns the roles: an advanced user approves entity links, an IT Expert collects the S3 credentials, and the Bank Prudential Reporting Responsible maintains the mailing list that the reminders use.

File naming

The mandatory pattern is TYPE-ENNNNNNNN-YYYY-MM-SUBTYPE-A-R.zip. TYPE is the constant CFEREP, E is B for the reporting entity, NNNNNNNN is the eight-digit CSSF code, YYYY-MM is the end of the reference period, SUBTYPE is COREPX for the quarterly COREP own funds module (COREPY is the yearly COREP OF subtype), A is the accounting version (C, N, L or S) and R is the report version (D or N). Applied to the CSSF’s example entity B00000999, a solo March file from a bank without foreign branches would be named CFEREP-B00000999-2026-03-COREPX-L-N.zip, and its consolidated counterpart would carry C in the accounting version position. For S3 the name also takes an underscore and a UUID under RFC 4122, and a file cannot be uploaded twice with the same UUID.

Taxonomy and format

The taxonomy is tied to the reference date, including for resubmissions. The user guide lists the COREP_OF entry points by period: version 3.0.0 from 2021-06 to 2023-05 with separate individual and consolidated entry points, 3.2.0 from 2023-06 to 2025-02, 4.0.0 from 2025-03 to 2026-02, and 4.2.0 from 2026-03, the last one a JSON entry point. The rule that follows matters most in a correction cycle. Any submission or resubmission against a .xsd entry point goes in XBRL-XML, as a .zip holding one .xbrl file with the same name, while a .json entry point requires XBRL-CSV, as a .zip holding one folder with the same name and the standard report package structure. A corrected December 2025 SOLV file therefore goes in XBRL-XML under 4.0.0, while a file for March 2026 or a later period goes in XBRL-CSV under 4.2.0, an entry point for which the user guide does not yet give an end date.

Each instance covers one reporting entity, one reporting period, the appropriate unit, one audit status and one consolidation status, so solo and consolidated SOLV are always separate files. The CSSF accepts no partial reports: any new instance replaces every earlier sending of the same report. Corrective data are accepted for the previous three years.

Filing indicators

Since EBA filing rules version 5.2, missing filing indicators are not allowed. From submission date 1 January 2023, irrespective of reference date and including resubmissions, every template must be declared explicitly positive or negative. The CSSF’s note on filing indicators gives SOLV-specific examples: C_01.00 is always expected with filed=”true” for a bank reporting COREP solvency, C_06.01 is always negative for an entity reporting on an individual basis, a bank using only the standardised approach for credit risk reports C_08.01 negatively, and a bank that reports settlement and delivery risk in C 02.00 row 0490 must report C_11.00 as filed=”true”. The CSSF’s January 2023 revision of the note corrected that standardised approach example: the earlier wording told such a bank not to report the C_08.01 indicator, and the tracked change makes it report the indicator negatively.

The ECB derives the expected indicators by applying the rules in the CSSF’s “Identification of reporting requirements” file to each bank’s masterdata: consolidation scope, risk methods, accounting framework, reporting waivers and other attributes. The CSSF does not share that masterdata individually and asks banks to report changes in their activities or characteristics to their line supervisor immediately.

For testing there is a pre-production eDesk environment and an “Echo” S3 bucket that returns a dummy feedback file. After CSSF processing, files of entities covered by the ECB decision on supervisory data go to the ECB automatically, and the global CSSF and ECB status is accepted only when both accept. Files the CSSF does not pass on, mainly those of third-country branches, show an empty ECB status and a global status of N/A.

Validation of SOLV files: EBA rules, CSSF checks and the causes of rejection

The user guide sets three layers of control for every file: technical checks on the name, entity and period; EBA taxonomy controls, meaning the validation rules of the applicable framework; and the EBA filing rules. The CSSF’s plausibility checks (the v_cssf series) generate automatic rejection messages when triggered, and for files passed to the ECB the ECB runs its own validation, including completeness checks on filing indicators and the additional data quality checks of its Expert Group on Data Quality (EGDQ).

The formal verification rules annexed to the user guide list the technical rejection codes.

  • RULE001: the file name is not compliant with the naming convention.
  • RULE002: the file is larger than 20 MB.
  • RULE003: the .zip does not contain exactly one XBRL file or one XBRL-CSV structure.
  • RULE004: the entity linked to the logged-in user does not match the entity in the file name.
  • RULE005: a file with the same name has already been received.
  • RULE008: the accounting version is not the one expected.
  • RULE009: a file already submitted for the period has not yet been processed.
  • RULE010: the entity is not authorised to send this type of report for the period.
  • CSSF_1: the entry point does not match the reporting type and period.

Once a file passes those checks, its status depends on what the validation raised. At least one error means NOT-ACCEPTED and a corrected file. Warnings only means NOT-ACCEPTED with “warning only” set to yes, and each warning must be explained through the eDesk dashboard. The CSSF then either accepts the report or asks for a corrective one. The handbook calls warnings “equally binding” to errors in the sense that reporters must analyse them and revise the data where needed, even though some warnings do not apply to every reporter or every reference date.

Two data rules sit underneath. Article 23(1)(a) excludes information that is not required or not applicable, so the handbook asks banks not to generate zeros for templates with positive filing indicators when they have no data, except where an EGDQ check requires an explicit “interesting zero”. Where the filing indicator is negative or absent, no values may be sent, zeros included, or the CSSF is likely to answer with error EFR 1.7.1. For XBRL-CSV the EBA filing rules add that a .csv data file must not exist for a template whose filing indicator is negative.

EGDQ outcomes are handled proportionately. For significant institutions an EGDQ error always requires a resubmission, and an EGDQ warning requires either a resubmission or, where resubmission is impossible, an explanation. For less significant institutions the CSSF may request a resubmission where an error is material.

The two CSSF validation rule lists

The CSSF publishes two validation rule spreadsheets that do different jobs. The first, “Deactivated validation rules and EBA small validation packages COFREP”, maps each EBA list of deactivated rules, and each EBA small validation package, to the date from which it applies to reports submitted to the CSSF. The CSSF’s current spreadsheet records the CSSF applicability dates for EBA deactivated-rule lists and small validation packages, including the 12 December 2025 EBA list (applicable at the CSSF from 5 January 2026). Those CSSF applicability dates should be checked in the current spreadsheet before deciding whether a rule is active for a particular submission. A rule is switched off for a SOLV file from the CSSF’s date, which can trail the EBA publication by days or weeks. Our explainer on CSSF COFREP validation rules and EBA small packages covers that file in detail.

The second list, “CSSF status of problematic EBA validation rules”, records EBA rules the CSSF considers problematic and sets out, rule by rule, how it treats them, from citing the relevant EBA Q&A to disregarding a rule until the EBA amends it. Its version 27.0 of 9 August 2021 has not been revised since. Two entries in its “Current” sheet touch SOLV. For v8730_m on C 09.04, the CSSF notes that the rule flags a zero own funds requirement in row 0090 even where the exposures in rows 0030 and 0040 carry a 0% weight, and asks banks in that case to inform its reporting team; where rows 0030, 0040 and 0090 all hold zeros, it suggests replacing the zeros with blank cells. For v6252_m on C 03.00, it records that the EBA formula tests the CET1 ratio against 0.0045 where 0.045 was intended. Both entries date from framework 3.0, so the current EBA rule list is the place to check whether either rule still exists in that form.

Caveats for SOLV filers: thresholds, masterdata and overlaps with other modules

Several SOLV templates depend on thresholds in Implementing Regulation 2024/3117, and Article 4(3) sets a common rhythm for them: reporting starts on the reference date after a threshold has been exceeded on two consecutive reference dates, and may stop after it has been undershot on three consecutive reference dates.

  • C 09.01 and C 09.02 are due where non-domestic original exposures reach 10% of total domestic and non-domestic original exposures, measured with C 04.00 rows 0850 and 0860 (Article 5(2)).
  • C 32.03 and C 32.04 are due for institutions applying the core approach to prudent valuation that exceed the threshold in Article 4(1) of Delegated Regulation (EU) 2016/101 (Article 5(3)).
  • C 14.00 and C 14.01 on securitisation are due except where the institution is part of a group in the same country in which it is subject to own funds requirements (Article 6(2)).
  • C 33.00 is due where general government exposures reach 1% of the total carrying amount of debt securities and loans and advances, with the full country breakdown where domestic exposures are below 90% (Article 6(3)).
  • C 17.01 and C 17.02 depend on the operational risk approach the institution used in December 2024 and on whether it is a large institution (Article 6(4)); Article 4(3) does not list Article 6(4), and Article 4(2) sets its own start date for large institutions.

Article 4(4) overrides the two-date rhythm for institutions that, in the six months before the reference date, were newly authorised as credit institutions, became subject to the CRR as investment firms, or resulted from a merger or split.

The C 04.00 non-domestic exposure rows reach beyond SOLV. The CSSF’s filing indicator note uses the same 10% test to illustrate a threshold-based template in FINREP: a bank above it reports F 20.04 with filed=”true”, a bank below it with filed=”false”. A sustained move in those two COREP cells can therefore change a FINREP filing indicator too, on the Article 4(3) rhythm.

Some national settings shape the figures without appearing in the ITS. The CSSF’s guidance on the combined buffer rows, CSSF Regulation No 15-01 on the institution-specific countercyclical buffer, and the default P2R composition of Article 104a(4) CRD, which applies “if not decided differently by the competent authority”, all feed C 03.00, C 04.00 and C 09.04. The CSSF documents on SOLV are silent on how a solo waiver under the CRR changes the SSOLV perimeter; the filing indicator note mentions reporting waivers only as one of the masterdata attributes that drive the expected filing indicators.

Temporary regimes also remain in the file: until 31 December 2026, market risk own funds requirements are reported under Article 5(12) of Implementing Regulation 2021/451 (Article 5(4) of 2024/3117, as amended), and C 18.00 to C 24.00 still appear in the handbook’s SOLV tables.

Changes to SOLV reporting: operational risk, FRTB and EBA framework 4.4

The template set has moved with each CRR package. CRR2, together with the non-performing exposure backstop added to the CRR in 2019, brought Implementing Regulation 2021/451 and, from 30 June 2021, new C 08, C 34 and C 35 templates for IRB, counterparty credit risk and non-performing exposure loss coverage. CRR3 brought Implementing Regulation 2024/3117 from the 31 March 2025 reference date, adding the output floor, revised credit risk templates, crypto-asset exposures and the new CVA approaches.

Operational risk followed later. Implementing Regulation (EU) 2025/2475 of 8 December 2025 was published in the Official Journal on 9 December 2025 and entered into force on 29 December 2025. It replaced C 16.01 and added C 16.02 (business indicator component), C 16.03 (losses, expenses, provisions and other financial impacts from operational risk events) and C 16.04 (subsidiaries subject to Article 314(3) CRR). EU parent institutions report C 16.04 quarterly on a consolidated basis (new Article 7(c)). On 17 December 2025 the EBA told banks to report C 16.01 on the updated release 4.2 tables from the March 2026 reference date, without the “other operating expenses” information for that date, and set June 2026 as the first mandatory reference date for C 16.02 to C 16.04, with voluntary reporting possible from March 2026. The Luxembourg angle is covered in our note on CRR3 operational risk reporting in Luxembourg.

Framework 4.2, whose final technical package the EBA published on 25 November 2025, completed the move to DPM 2.0 and the new glossary for all modules except DORA. The EBA framework page states that the COREP OF module is reported under the 4.2 package from the 03/2026 reference date.

Market risk is next. The FRTB own funds requirements now apply from 1 January 2027 after two Commission delegated acts under Article 461a CRR, including Delegated Regulation (EU) 2025/1496, and Implementing Regulation 2025/2475 extended the old market risk reporting to 31 December 2026 to match. On 4 June 2026 the Commission adopted a third delegated act introducing temporary operational relief measures and targeted multipliers for the FRTB framework. It was subsequently published as Commission Delegated Regulation (EU) 2026/1221 in the Official Journal on 11 September 2026, entered into force on 12 September 2026 and applies from 1 January 2027. The EBA’s note on that act identifies 12 May 2027 as the deadline for reporting the 31 March 2027 reference date. Separately, Article 24(2) of 2024/3117 fixes the first reference date for reporting the composition of the trading book as the last business day of the quarter in which the FRTB approaches become applicable.

Further out, the EBA published the draft technical package for framework 4.4 in July 2026 and announced the final package for September 2026; its framework 4.4 page expects the framework to apply from Q4 2026 and places the COREP OF amendments in phase 2 with an expected first reference date of 09/2027. The listed items are operational losses, transitional arrangements, simplification, a module split linked to financial year end, boundary and market risk, and the integration of stress tests. The draft package is discussed in our piece on EBA reporting framework 4.4. For third-country branches, the EBA’s final technical package for framework 4.3, published on 9 July 2026, carries the specifications for the supervisory reporting standards since published in the Official Journal as Commission Implementing Regulation (EU) 2026/1757, which applies from 28 March 2027, with a first reference date of 31 March 2027. The CSSF handbook and user guide are silent on whether the CSSF will change the SSOLV requirement for those branches once that reporting applies.

Frequently Asked Questions

Our financial year does not end on 31 December. Do the SOLV reference dates move with it?

Only in part. Article 2(3) of Implementing Regulation 2024/3117 allows institutions permitted by national law to report on a non-calendar year-end to adjust the reference dates for financial information, for the information reported under Article 8 and for G-SII data, with remittance dates shifted to keep the same interval (Article 3(3)). The core own funds templates under Articles 5 to 7 are not in that list, so they stay on the calendar quarter-ends.

We were authorised as a credit institution four months before a reference date. Do the threshold-based SOLV templates apply at once?

Article 4(4) and (5) replace the two-consecutive-dates rule for newly authorised credit institutions, investment firms newly subject to the CRR, and entities resulting from a merger or split. An institution that already exceeds a threshold on its first reference date reports the templates subject to that threshold for both the first and the second reference dates. One that exceeds it only on the second reference date reports from the second.

We are opening our first foreign branch. What changes in the SOLV file?

The handbook’s SSOLV table moves the bank from accounting version L to version N (head office plus foreign branches), and individual FINREP moves from the single L version to L, S and N. The CSSF’s filing indicator note asks for such changes to be reported to the line supervisor immediately because they move the expected filing indicators, and RULE008 is the check that rejects a file whose accounting version is not the one expected.

Can we still correct a SOLV file from several years ago?

The CSSF user guide accepts corrective data for the previous three years, and the correction must use the taxonomy version that applied to the original reference date. It is silent on corrections older than three years and gives reportingbanques@cssf.lu as the contact for business questions.

We think an EBA validation rule that blocks our SOLV file is wrong. Can the CSSF switch it off for us?

Circular CSSF 14/593 sets the route: the bank submits a question through the EBA Q&A tool and sends a copy with the EBA’s Q&A number to reportingbanques@cssf.lu. The circular adds that the CSSF suspends a challenged EBA rule only once the EBA has amended it. A challenge to a CSSF plausibility rule goes to the same address by email.

The CSSF sent us a new SREP decision in November. When does the new P2R appear in C 03.00?

The CSSF’s additional guidance states that a new or amended Pillar 2 add-on communicated up to the end of year N and applicable from 1 January of year N+1 is reflected in the March COREP of year N+1. The December file of year N still carries the previous P2R.

Key Takeaways

  • Map each SOLV file to its accounting version before quarter-end: N for a Luxembourg bank with foreign branches, L for one without and for third-country branches, C for the consolidated return.
  • Build any file for a reference period from March 2026 in XBRL-CSV against the entry point the CSSF user guide lists for that period (COREP_OF 4.2.0 from 2026-03, end date not yet set), and route corrections of earlier periods through XBRL-XML on the taxonomy of that period.
  • Upload early enough to leave working days for warning explanations: an on-time file whose warnings are still unexplained at the deadline triggers the same reminder as a missing one.
  • Keep the Responsible level 1 and level 2 contacts in the eDesk mailing list current, and name who drafts warning explanations before each remittance date.
  • Before treating an EBA rule as switched off for a SOLV file, check its applicability date in the CSSF deactivation file, and read the August 2021 problematic-rules list as framework 3.0 guidance to recheck against the current EBA rules.
  • Recheck the C 04.00 rows 0850 and 0860 ratio every quarter: it decides C 09.01 and C 09.02 in SOLV and the F 20.04 filing indicator in FINREP.
  • Plan for two dated changes: FRTB-based market risk from the 31 March 2027 reference date and the COREP OF amendments of framework 4.4, expected from 09/2027.

Sources and References

Preparing the next SOLV file for the CSSF

The next SOLV file falls due on the first remittance date after the quarter now closing, or the next working day if that date is a weekend or a Luxembourg public holiday. Besides a validation run with no errors, three points need checking before the remittance deadline: a file name and accounting version that match the bank’s masterdata, a filing indicator for every template in the COREP_OF module, and an explanation submitted in eDesk for every warning. The artifact to prepare is the explanation log, template by template, drafted before upload.

Disclaimer: The information on RegReportingDesk.com is for educational and informational purposes only. It does not constitute legal, regulatory, tax, or compliance advice. Always consult your compliance officer, legal counsel, or the relevant supervisory authority for guidance specific to your institution.

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