AWS Backup does not natively support global deduplication or change block tracking across backups. As a result, even traditional incremental or differential backup strategies (e.g., daily incremental, weekly full) can accumulate redundant data. Over time, this leads to higher-than-necessary storage usage and cost — especially in environments with frequent backup schedules or large data volumes that only change minimally between snapshots. While some third-party agents can implement CBT and deduplication at the client level, AWS Backup alone offers no built-in mechanism to avoid storing unchanged data across backup generations.
Backups are billed per GB-month of backup storage. This includes both warm storage (primary backup copies) and cold storage (if lifecycle policies transition backups to cold tiers). Charges are accrued for each full or incremental backup, regardless of data change volume. Lack of deduplication or CBT at the platform level can inflate backup sizes and recurring costs.
