Amazon ElastiCache Supported Engines (2026)
ElastiCache is AWS's managed in-memory service, and the engine you pick decides your license, your feature set, and your bill. The 2026 reality that trips people up: the Redis OSS engine has not moved past 7.1, so "ElastiCache for Redis" is a legacy track, while Valkey carries the current open source releases.
Sources: AWS ElastiCache for Valkey launch, Redis 7.1 GA on ElastiCache, ElastiCache pricing. Verified July 2026.
Why "ElastiCache for Redis" is a legacy track
When people search for "Amazon ElastiCache for Redis" they usually expect it to track upstream Redis. It does not. The Redis OSS engine on ElastiCache has been frozen at version 7.1, which reached general availability on ElastiCache in November 2023. AWS never shipped Redis 7.2 or 7.4 as a Redis OSS engine, and after Redis Inc relicensed Redis under SSPL (March 2024) AWS pivoted its investment to the Valkey fork. So the newest open source engine you can run on ElastiCache is Valkey (up to 9.1), not Redis.
The practical consequence is feature scope. Redis 8.0 (May 2025) put vector sets (VADD/VSIM, HNSW similarity search) into the core data model. Those commands are not available on ElastiCache, because ElastiCache's Redis OSS engine stopped at 7.1 and Redis 8 is not offered here at all. If you need Redis 8.0's core vector sets on AWS, you are looking at self-hosting or Redis Cloud, not ElastiCache. Valkey delivers vector similarity too, but through the separate valkey-search module rather than a core data type.
This is why AWS steers new clusters to Valkey and why the "for Redis" label is misleading in 2026: choosing the Redis OSS engine gets you a four-year-old release on a maintenance track, while Valkey gets you the current line at a lower price. The one honest reason to stay on Redis OSS is an existing 7.x deployment you are not yet ready to migrate; the in-place migration to Valkey is a few clicks with zero data loss when you are.
Which engine to pick
FAQ
What engines does Amazon ElastiCache support?
ElastiCache supports three engines: Valkey, Redis OSS, and Memcached. Valkey is the default and recommended engine for new deployments since October 2024. Redis OSS remains selectable but is frozen at version 7.1. Memcached remains for pure ephemeral cache workloads. AWS MemoryDB is a separate, Valkey-based durable service and is not an ElastiCache engine.
What is the latest Redis version on ElastiCache?
The Redis OSS engine on ElastiCache is frozen at version 7.1, which went GA on ElastiCache in November 2023. AWS has not shipped Redis 7.2, 7.4, or Redis 8 as a Redis OSS engine version. Redis 8.0 features such as core vector sets (VADD/VSIM) are therefore not available on ElastiCache. For current-generation open source on ElastiCache, the forward path is the Valkey engine (up to 9.1), not Redis OSS.
Is Valkey the default engine on ElastiCache?
Yes. Since ElastiCache for Valkey went GA in October 2024, Valkey is the default engine recommendation for new clusters. It is priced 20% lower than Redis OSS on node-based (self-designed) clusters and 33% lower on ElastiCache Serverless, per the AWS ElastiCache pricing page. Existing Redis OSS clusters can migrate in-place to Valkey with zero data loss.
Which ElastiCache engine should I choose?
For most new builds, Valkey: it is the current open source engine (up to 9.1), BSD-licensed, and the cheapest of the three per node. Choose Memcached only for a pure ephemeral cache where you need no replication or persistence and want maximum cache per dollar. Choose Redis OSS only if you have an existing 7.x deployment you are not ready to migrate; it is a legacy track with no path to Redis 8 on ElastiCache.
Does ElastiCache Memcached support the latest Memcached?
ElastiCache for Memcached tracks the 1.6 line. It added AWS-specific features ahead of upstream, notably TLS support (2023) before stable TLS landed in upstream Memcached. It has no replication, no persistence, and no snapshots; scaling is horizontal via a node pool with client-side consistent hashing through an auto-discovery config endpoint.