Many environments continue using io1 volumes for high-performance workloads due to legacy provisioning or lack of awareness of io2 benefits. io2 volumes provide equivalent or better performance and durability with reduced cost at scale. Failing to adopt io2 where appropriate results in unnecessary spend on IOPS-heavy volumes.
Provisioned IOPS volumes are billed based on the amount of storage (per GB) and the number of provisioned IOPS. While io1 and io2 share the same baseline pricing, io2 introduces **tiered IOPS pricing**—offering a lower per-IOPS rate once volumes exceed thresholds such as 32,000 IOPS. For high-throughput workloads, this tiering makes io2 significantly more cost-effective.
