ISDA has published the ISDA SIMM® Methodology, version 2.8+2506, which is effective from December 6, 2025.
This version of the SIMM includes updates based on the calibration of the main delta risk weights and other parameters using data up to June 30, 2025, following the industry backtesting of the methodology. This marks the second SIMM version published under the new semiannual calibration cycle introduced in 2025.
The ISDA SIMM methodology remains a central part of the SIMM Governance Framework that ISDA SIMM users are expected to adhere to.
The effective date of December 6, 2025 means that ISDA SIMM users should use SIMM version 2.8+2506 to calculate the initial margin for Close of Business (COB) on Friday December 5, 2025 onwards. This means that the first day for exchange of initial margin calculated using SIMM version 2.8+2506 would be on Monday December 8, 2025.
Documents (1) for ISDA Publishes ISDA SIMM® Methodology, Version 2.8+2506
Latest
Paper on Proposal 6 on Margin Transparency
On November 16, ISDA published a document that looked at proposal 6 in the final Basel Committee on Banking Supervision (BCBS), Committee on Payments and Market Infrastructures (CPMI) and International Organization of Securities Commissions (IOSCO) report on margin transparency. Proposal...
Tender Issued for DC Administrator Role
ISDA and the Credit Derivatives Governance Committee have issued an invitation to tender for an independent regulated entity to serve as the administrator for the Credit Derivatives Determinations Committees (DCs), which includes assuming the role of DC secretary. The DC...
ISDA SIMM: The Standard for IM Calculations
The ISDA Standard Initial Margin Model (ISDA SIMM) plays an important role in ensuring margin calculations are consistent, transparent and aligned with global best practices and regulatory requirements. Since its launch in 2016, the model has been rigorously tested, regularly...
ISDA In Review – October 2025
A compendium of links to new documents, research papers, press releases and comment letters published by ISDA in October 2025.