MMF Weekly Liquid Assets: CSSF Finalises 20% and 40% Levels

The CSSF published its final guidance on MMF weekly liquid assets on 30 October 2026, and the numbers did not move. The CSSF expects Luxembourg money market funds to align their liquidity risk frameworks and weekly liquid assets (WLA) with market resilience levels of 20% for variable net asset value (VNAV) funds and 40% for public debt constant net asset value (public debt CNAV) and low volatility net asset value (LVNAV) funds. Under the guidance, a manager whose fund sits below its level for more than 10 business days, or who expects a prolonged or substantial deviation, notifies the CSSF.

The final document, which carries the CSSF’s feedback statement on its 8 June 2026 consultation, adds a three-month implementation period, confirms that the notification duty starts on day 11, and states that there are no additional reporting requirements besides the notification.

Related reading: our analysis of the CSSF consultation on MMF weekly liquid assets

Key dates in the CSSF MMF liquidity timeline

• 8 June 2026: CSSF consultation paper published, in coordination with the European Commission, the French AMF and the Central Bank of Ireland.
• 3 August 2026: consultation closed. The CSSF received eleven written responses, from seven asset management firms and four representative bodies.
• 30 October 2026: final guidance and feedback statement published.
• Three months from publication: implementation period. Counting from 30 October 2026 points to the end of January 2027. That end date is my calculation; the CSSF gives no end date.
• Before the implementation period ends: the CSSF publishes on its website the notification process for Luxembourg-domiciled MMFs.

What the final MMF weekly liquid assets text changed, and what it kept

The CSSF describes its edits as slight clarifications in the last two paragraphs of section 2.1 on liquidity risk management. Setting those paragraphs against the consultation text, I count two. The enhanced-vigilance paragraph now applies when WLA approach or fall below the market resilience levels “on any business day”. The notification paragraph now opens with the duty to notify, places the trigger after it, and gives the content requirement its own sentence: the notification shall contain relevant explanations and justifications, including, where relevant, the measures taken under Article 28(4) and (5) of the MMFR if stress tests reveal a vulnerability.

The substance survived industry comment. Several respondents asked for the levels to be treated as “supervisory reference indicators rather than de facto regulatory minimums”, and one suggested that supervisory engagement should not start automatically at the 40% threshold. The CSSF kept the levels and proceeded with the Part 2 engagement text as proposed, answering the buffer-usability concern through the Commission’s FAQs.

The notification duty from day 11

The trigger has two limbs. A manager notifies the CSSF where an MMF falls below its market resilience level for a period exceeding 10 business days, or where the manager expects a prolonged and/or substantial deviation. The feedback statement pins down the first limb: the obligation is triggered after the 10-business-day period, from day 11 onwards. On my reading, the second limb carries no waiting period, so a manager who expects a fund to stay well below 40% can owe a notification before day 11 arrives.

Day 10 matters on the supervisory side as well. Section 2.2 states that where a fund’s WLA sit below the market resilience level for 10 business days and that level is not justified by the manager’s liquidity risk management processes and systems, the CSSF shall review the information at its disposal. The CSSF will assess case by case whether a deviation is justified, given differences in investment strategy, liquidity profile, redemption policy and market conditions. Respondents asked for a common definition of “justified” across national authorities; the final text gives none.

The guidance also leaves “business day” undefined, and it names no form, portal or template for the notification.

Reporting teams get a notification and no new return

For reporting teams, the operative sentence in the feedback statement is that there are no additional reporting requirements besides the notification requirement. A few respondents had warned against duplicated reporting. The CSSF keeps its discretion to request additional information where needed in its supervisory engagement with MMF managers.

The data list shows what such a request could contain. At the onset of stressed market conditions affecting MMFs, the CSSF may request more frequent data, which could include key risk indicators, daily reporting and data points such as NAV, net subscriptions, WAM, WAL, the daily and weekly liquidity buffers and, where applicable, the difference in basis points between constant NAV and shadow NAV. Periodic engagement may add qualitative questions, for example on quarter-end effects and main active counterparties.

The notification is one of two routes into increased supervisory scrutiny. The other is the CSSF’s own analysis of MMF reporting and related supervisory work. I read that as the Article 37 MMFR report, which managers file at least quarterly (at least annually for an MMF whose assets under management in total do not exceed EUR 100 million) and which includes liquidity among its portfolio indicators. The CSSF’s view of a fund’s liquidity therefore does not rest on the notification alone.

Buffers stay usable, and the levels carry no LMT trigger

Several respondents asked the CSSF to state explicitly that liquidity buffers, both the MMFR minimums and the market resilience levels, may be used during stress periods. The CSSF’s response is that the guidance should be read with the Commission’s 2026 MMF Report (COM(2026) 350) and its FAQs, Commission Notice C(2026) 2510 final, both dated 11 May 2026 and covered in our review of the EC Money Market Fund Regulation report. FAQ No. 3 says the MMFR provisions envisage that a portfolio may fall below the regulatory limits, including the minimum liquid asset requirements, and that increased redemptions in stressed market conditions are to be seen as beyond the manager’s control, while noting that such reasons will arise very rarely.

The CSSF adds that the guidance does not foresee or mention any automatic link between the market resilience levels and liquidity management tools. A fund dipping under 40% has no tool to activate on that account alone. For public debt CNAV and LVNAV funds, the MMFR Article 34 measures on a liquidity shortfall are unchanged, and the Commission’s notice (C(2026) 2510 final) adds that the new UCITS and AIFMD liquidity management tool framework further strengthens the liquidity management of EU MMFs; the wider framework is covered in our guide to AIFMD II liquidity management tools.

The statutory floors underneath are unchanged. Article 24 of the MMFR requires public debt CNAV and LVNAV funds to maintain at least 10% daily liquid assets and 30% weekly liquid assets, compared with 7.5% and 15% for short-term VNAV funds. Article 25 sets the corresponding minimums at 7.5% and 15% for standard MMFs, which can only take the VNAV form.

The calculations cover the specified daily or weekly maturing assets, qualifying reverse repurchase agreements and withdrawable cash. Certain additional instruments may also count towards weekly liquidity, subject to the conditions and caps in Articles 24(1)(g) and (h) and 25(1)(e). The 20% and 40% supervisory resilience benchmarks do not replace these statutory requirements. The guidance applies its 20% level to VNAV MMFs without separating short-term from standard funds, and leaves the daily liquidity requirement at its MMFR level.

What the three months are for

The CSSF grants the implementation period to facilitate funds’ orderly alignment with the market resilience levels, after some respondents asked for a transitional period. The feedback statement frames the expectation as liquidity risk frameworks and WLA levels aligned with the market resilience levels, and the respondents who asked for the period wanted room for portfolio adjustments. On the framework side, section 2.1 asks managers to account for the 20% and 40% levels in Article 28 stress testing and to have mechanisms that alert them to funds operating below the internal minimum levels in their monitoring systems.

Article 28 supplies the hard edges. Where a stress test reveals a vulnerability, Article 28(4) requires the manager to draw up an extensive report and a proposed action plan, to take action where necessary to strengthen the fund, and to inform the competent authority immediately of the measures taken. Under Article 28(5) the board approves the final action plan, and the report and plan go to the competent authority for review.

The 2026 MMF Report, as cited in the guidance, found average levels of at least 29% WLA for VNAV funds and at least 54% for public debt CNAV and LVNAV funds. Those market averages do not establish an individual fund’s liquidity requirement. A VNAV fund holding WLA between the 15% statutory minimum and the 20% market resilience benchmark should assess its liquidity position, investor-redemption profile and stress-test results to determine whether a portfolio change is warranted. Falling below the supervisory benchmark does not, by itself, establish a breach of the statutory minimum.

Frequently Asked Questions

Does the CSSF process cover an Irish- or French-domiciled MMF run by a Luxembourg management company?

The CSSF has said it will publish its notification process for Luxembourg-domiciled MMFs before the implementation period ends. Under Article 2(17) of the MMFR, the competent authority of a UCITS MMF is the authority of the UCITS home Member State, and for an EU AIF that of the AIF’s home Member State. The Central Bank of Ireland (consultation CP168) and the French AMF consulted on their own national guidance in the same coordinated exercise, so on my reading an Irish or French fund looks to its own authority’s text and process.

Does the buffer flexibility extend to a public debt CNAV or LVNAV fund whose weekly maturing assets fall below 10%?

FAQ No. 3 lets these funds use their buffers under stressed conditions without activating tools in the Article 34(1)(a) situation, and states that this does not apply to Article 34(1)(b). Below 10% weekly maturing assets, Article 34(1)(b) requires the manager to inform the board immediately, and the board to undertake a documented assessment and apply liquidity fees on redemptions, a suspension of redemptions of up to 15 working days, or both, documenting its reasons. Article 34(3) then requires the board to promptly provide details of its decision to the competent authority, an obligation separate from the market resilience notification.

If a fund recovers above its level on day 9 and falls back below on day 10, does the count restart?

The guidance leaves this open. It ties notification to a period exceeding 10 business days and supervisory intensity to the duration and frequency of deviations, without saying whether separate periods below the level are added together. The forward-looking limb still applies whenever a prolonged or substantial deviation is expected.

Related Articles

• CSSF MMF Weekly Liquid Assets Consultation: the June 2026 proposals and the Article 34 measures in detail.
• EC MMF Regulation Review: the Commission’s 2026 review behind the market resilience levels.
• CSSF MMFR FAQ Update: what Version 5 of the CSSF’s MMFR FAQ changed.
• AIFMD II Liquidity Management Tools: the harmonised LMT toolkit for UCITS and AIFs.
• CSSF LMT Activation Module: how Luxembourg funds notify a redemptions-only suspension.

Key Takeaways

• Classify each fund before building alerts: 20% covers short-term and standard VNAV funds alike, 40% covers public debt CNAV and LVNAV funds.
• Run two notification paths: an automatic one after more than 10 business days below the level, and a judgement-based one whenever a prolonged or substantial deviation is expected.
• Write the business-day calendar and the treatment of interrupted dips into the liquidity procedures, since the guidance defines neither.
• Prepare for request-driven data in stressed markets, such as daily reporting on NAV, WAM, WAL and the liquidity buffers; the notification is the only standing addition.

Sources and References

• CSSF, Final Guidance on Money Market Fund (MMF) Weekly Liquid Asset Levels, including CSSF feedback statement to the public consultation (30 October 2026): CSSF final guidance (PDF) and CSSF document page
• CSSF, Guidance on Money Market Fund Weekly Liquid Asset Levels, Consultation Paper (8 June 2026): CSSF consultation paper (PDF)
• Regulation (EU) 2017/1131 on money market funds (MMFR), Articles 2, 24, 25, 28, 34 and 37: EUR-Lex CELEX:32017R1131
• European Commission, Report on the adequacy of Regulation (EU) 2017/1131, COM(2026) 350 final (11 May 2026): Commission 2026 MMF Report (PDF)
• European Commission, Commission Notice C(2026) 2510 final, interpretation of the MMFR (FAQs), 11 May 2026: Commission MMF FAQs (PDF)
• Central Bank of Ireland, CP168, Consultation on Guidance on Money Market Fund Weekly Liquid Asset levels (8 June 2026): Central Bank of Ireland CP168

Before the CSSF implementation period closes

The next document to watch is the CSSF’s notification process for Luxembourg-domiciled MMFs, due on its website before the three months run out. By then a manager’s monitoring set-up would need to classify each fund against 20% or 40%, flag a dip on any business day, count business days below the level, record whether a prolonged or substantial deviation is expected, and hold the Article 28 stress-test evidence a notification would have to explain.

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.