Announcing: Minimum billable object size for cooler storage tiers

For storage accounts with Azure Blob or Data Lake Storage (ADLS) we are introducing a minimum billable object size for the cool, cold and archive access tiers of 128KiB. Objects on those tiers that are smaller than 128 KiB will be billed as 128 KiB objects at the rate of the corresponding tier. Billing occurs on the existing capacity billing meters (data stored). There is no change to transactions. This billing behavior will be introduced in two stages: July 1, 2026: This new billing behavior applies to all new storage accounts created on or after this date. There is no change for existing storage accounts at this time. July 1, 2027: This new billing behavior applies to all storage accounts. The hot access tier continues to have no minimum object size. To reduce potential cost impact, we recommend packaging small objects into larger objects before moving data to cooler tiers, or using Smart Tier (GA) to automatically keep small objects on the hot access tier. The Blob Capacity metrics are introducing new Blob Types (BlockBlobSmall and Azure Data Lake Storage Small) to support this change. [Learn more](https://learn.microsoft.com/en-us/azure/storage/blobs/access-tiers-overview#minimum-billable-object-size-on-cooler-tiers).