New Field betDelayModels Added to Historical Data Files from 17th August 2026

[Betfair Developer Program]

The new field betDelayModels will be available in the Betfair Historical Data service market files after the date 17/08/26

Please note that following field will be available on all messages where publish time is greater than or equal to 17/08/26 10:00 BST

Also note that files for markets that span across the point 17/08/26, 10:00 BST will contain market definition messages without this new field up until 17th of August 2026 10:00 BST and with the new field after17th of August 2026 10:00 BST

• "betDelayModels": [] or absence of this field, indicates - Only traditional model of bet delay enabled
• "betDelayModels": [PASSIVE] - Passive Delay enabled for the market
• "betDelayModels": [DYNAMIC] - Dynamic Delay enabled for the market
• "betDelayModels": [PASSIVE,DYNAMIC] - Both Passive and Dynamic delays enabled for the market

Please see the latest Betfair Historical Data feed specification document attached.

Kind Regards

Betfair Developer Program