AlI EBS snapshots show full size in the AWS EC2 console

Summary

Snapshots all appear full size, even though they are incremental.

Description

In AWS, EBS snapshots are incremental, but the “snapshot size” you’re looking at is often not a “physical bytes stored” number, so it can look like every snapshot is “full” even when AWS is only storing deltas.

Here’s what’s going on and how to sanity-check it.

Why snapshots look “full” in production

1) The console “Size” is typically the volume’s logical size

In the EC2/EBS snapshot views, the Size you see typically reflects the size of the source volume (GiB), not the amount of unique snapshot data stored for that snapshot.

So if you have a 500 GiB volume, every snapshot may show 500 GiB because that’s the logical volume size.

2) Incremental doesn’t always mean “small”

Even though snapshots are incremental, deltas can be large if:

• The workload rewrites lots of blocks (databases, log-heavy systems, temp files, swap).
• You do large-scale patching/updates.
• Filesystems rewrite metadata across the disk.
• Encryption/key rotation/rehydration patterns cause broad block churn.

So a snapshot can be “incremental” yet still store almost as much changed data as a “full” copy.

3) Storage is calculated across the entire snapshot chain

AWS stores only blocks that have changed since the last snapshot, but restoring any snapshot depends on blocks across the chain. The UI isn’t trying to represent that physical storage structure—so it’s misleading if you expect “incremental size” to be shown.

Confirmation Steps

A) Look at EBS snapshot billing (best indicator)

Go to Cost Explorer and check:

• EBS: Snapshots usage/cost trend
  If snapshots were truly “full copies” every time, you’d see storage explode linearly with snapshot count. If they’re incremental, the growth rate will correlate with the actual change rate.

B) Use CloudWatch metrics for the volume to estimate churn

Check the EBS volume metrics:

• VolumeWriteBytes / VolumeReadBytes
  A high write volume usually means higher snapshot-delta storage.

Also, please refer to this article:

Amazon-ebs-full-snapshot-size-information-console