Nordic TSOs to remove 'Indivisible Bids Allowed' attribute, make Minimum Quantity mandatory in aFRR/mFRR capacity markets from 24 November 2026

Nordic TSOs have finalized an implementation date (24 November 2026, applicable to operational date 25 November 2026) for a change to bid submission methodology in the Nordic aFRR and mFRR balancing capacity markets. The 'Indivisible Bids Allowed' bid attribute will be removed entirely, and the 'Minimum Quantity' attribute will become mandatory for every bid submitted. Under the new regime all bids are treated as divisible by default; BSPs wishing to submit an effectively indivisible bid must do so by setting Minimum Quantity equal to the offered quantity. A test environment for the new implementation will be available to Balancing Service Providers (BSPs) from 15 September 2026 across all submission channels (manual UI entry, file upload, and ECP).

This changes the core bid data model BSPs must use to participate in Nordic balancing capacity markets, requiring updates to internal bidding systems, algorithms and processes ahead of a hard go-live date. Making Minimum Quantity mandatory and eliminating the separate indivisibility flag standardizes and makes more explicit how partial acceptance of capacity bids is handled, which can affect BSP bidding strategy, capacity market clearing outcomes, and ultimately balancing capacity procurement efficiency across the Nordic synchronous area.

This is a bid-attribute/data-model reform rather than a pricing or allocation methodology change, but it has real market-design consequences: by folding indivisibility into the Minimum Quantity field, the Nordic TSOs simplify the bid schema while preserving the functional ability to submit indivisible bids (MQ = offered quantity). The default-to-divisible stance is likely intended to increase clearing flexibility and reduce the incidence of rejected/unmatched capacity due to indivisibility constraints, which can improve capacity market liquidity and price formation marginally. Because this is an operational/technical implementation change communicated directly by TSOs with a firm go-live date and a defined testing window, it sits squarely in the IMPLEMENTATION phase of the lifecycle — the design decision itself appears to have already been taken (referenced back to a March 2026 announcement) and this source communicates finalization and rollout logistics rather than open design choices. The main forward risk is BSP readiness: all submission channels (UI, file upload, ECP) must be validated by BSPs before the November go-live, making the September test-environment milestone operationally critical.

Nordic Balancing Model (NBM) — Implementation Guide for the Nordic FFR/aFRR/mFRR balancing capacity market

Test environment available for BSPs to test new bid submission implementation · 15 Sept 2026

Primary sources