Backup data transfer cost: what moving your backups actually costs

Quick answer

Backup storage is the cheap part. Moving backups is where the cost hides. Copying snapshots to a second AWS region costs about 0.02 dollars per GB, so a 10 TB cross-region copy runs about 200 dollars. Restoring or exporting backups to somewhere outside the cloud pays full internet egress at 0.09 dollars per GB, meaning a 10 TB restore to on-premises costs about 920 dollars. Backups sent to a third-party SaaS backup vendor pay the same internet rate. The practical guidance is keep copies incremental, keep restores in-region, and test restores on a subset.

Backup cost conversations almost always focus on storage class. Should the archive sit in Glacier Flexible Retrieval at 0.0036 dollars per GB-month or Deep Archive at 0.00099? That question matters, but it is often the smaller number. The larger number is what it costs to move the bytes, and movement happens at three moments: when you copy a backup somewhere else, when you restore it, and when you test that the restore works.

The three moments where transfer is billed

Moment	Typical rate	10 TB example
Backup within the same region	Free	0 USD
Copy to a second AWS region	0.02 per GB	about 200 USD
Restore within the same region	Free	0 USD
Export or restore to on-premises	0.09 per GB	about 920 USD
Backup to third-party SaaS	0.09 per GB	about 920 USD
Glacier Flexible retrieval (standard)	0.01 per GB	about 100 USD
Deep Archive retrieval (standard)	0.02 per GB	about 200 USD

Writing a backup to S3 or to a snapshot in the same region as the source costs nothing in transfer. That is why the in-region backup is nearly always the cheap one and why the disaster recovery copy is where the budget goes.

Incremental copies change everything

EBS snapshots are incremental after the first one. The initial snapshot of a 2 TB volume copies the full used capacity, but each subsequent snapshot copies only changed blocks. If the volume changes 3 percent per day, daily snapshots after the first move about 60 GB each. Copying those to a second region costs about 1.20 dollars per day, or roughly 36 dollars per month, against about 40 dollars for the initial full copy.

Cross-region snapshot copies preserve that incremental property as long as you copy into the same destination region repeatedly and keep the earlier copies. Delete the chain and the next copy is full again, which is how a routine retention cleanup can accidentally trigger a full multi-terabyte transfer. The same incremental logic underpins AWS Backup cost.

Retrieval fees are separate from transfer

Archive tiers charge a retrieval fee that is distinct from any data transfer. On S3 Glacier Flexible Retrieval, bulk retrieval is free, standard retrieval is 0.01 dollars per GB, and expedited is 0.03 dollars per GB. On Deep Archive, bulk is 0.0025 dollars per GB and standard is 0.02 dollars per GB. Glacier Instant Retrieval charges 0.03 dollars per GB with no delay. So restoring 10 TB from Deep Archive at standard speed costs about 200 dollars in retrieval, and if you then move it out of the cloud, another 920 dollars in egress on top.

The disaster recovery drill nobody budgets

A restore test is a real restore, and it is billed like one. Teams that commit to quarterly DR drills sometimes discover the drill costs more than a month of backup storage. A 20 TB estate restored from Deep Archive in a second region costs roughly 400 dollars in retrieval plus any compute for the restore targets, every quarter.

The sensible answer is not to skip the drill. It is to restore a representative subset, say 5 percent selected to cover every database and every critical file share, and to do a full restore annually rather than quarterly. Use bulk retrieval tiers where the drill has no urgency: bulk on Deep Archive at 0.0025 dollars per GB is eight times cheaper than standard, at the price of a 12 hour wait.

Third-party backup targets

Sending backups to a SaaS backup vendor or to a different cloud means paying full internet egress from the source cloud on every backup, not just the first. A 5 TB estate with 3 percent daily change sends about 150 GB per day, or 4.5 TB per month, which at 0.09 dollars per GB is about 414 dollars per month in egress before the vendor's own storage fee. Deduplication and compression at the agent, which commonly achieve 2:1 to 4:1 on mixed data, cut that proportionally. The cross-cloud version of this problem is covered in cross-cloud data transfer cost.

Designing a backup topology that is cheap to run

The pattern that works: primary backups in-region where transfer is free, lifecycle-tiered into archive storage for anything over 30 days, one cross-region copy for disaster recovery kept incremental and never broken, bulk retrieval for anything not time-critical, and partial restore tests as the routine with full tests as the exception. Above all, know the restore cost before you need it, because the worst time to discover a 920 dollar egress charge is during an incident. Price your backup infrastructure against the resource catalog.

FAQ

Does backing up data cost anything in transfer?

Writing a backup to S3 or to a snapshot in the same region as the source costs nothing in data transfer. Charges start when the backup moves elsewhere: a cross-region copy is about 0.02 dollars per GB on AWS, and an export out of the cloud entirely pays full internet egress at 0.09 dollars per GB, so a 10 TB export costs roughly 920 dollars.

How do incremental snapshots reduce copy cost?

EBS snapshots copy only changed blocks after the first one. A 2 TB volume changing 3 percent per day produces daily snapshots of about 60 GB, costing roughly 1.20 dollars per day to copy cross-region rather than about 40 dollars for a full copy. The incremental chain is preserved only if you keep copying into the same destination region and retain the earlier copies.

What are archive retrieval fees?

They are separate from data transfer. S3 Glacier Flexible Retrieval charges nothing for bulk, 0.01 dollars per GB for standard, and 0.03 dollars per GB for expedited. Deep Archive charges 0.0025 dollars per GB for bulk and 0.02 for standard. Glacier Instant Retrieval charges 0.03 dollars per GB. Restoring 10 TB from Deep Archive at standard speed is about 200 dollars in retrieval alone.

How much does a disaster recovery drill cost?

More than teams expect. Restoring a 20 TB estate from Deep Archive at standard retrieval costs roughly 400 dollars in retrieval fees per drill, plus compute for the restore targets. Running that quarterly can exceed a month of backup storage cost. Restoring a representative 5 percent subset quarterly with a full test annually, using bulk retrieval tiers, controls the expense without abandoning the practice.

What do third-party backup targets cost in egress?

Full internet egress on every backup, not just the first. A 5 TB estate with 3 percent daily change sends about 4.5 TB per month, which at 0.09 dollars per GB is roughly 414 dollars monthly before the vendor's own storage fee. Agent-side deduplication and compression, commonly achieving 2:1 to 4:1 on mixed data, reduce that proportionally.

How does C3X help with backup cost?

C3X prices backup infrastructure from Terraform before deployment, including snapshot schedules, cross-region copy configuration, storage classes, and the destinations that determine whether transfer is free or metered. Seeing a cross-region backup plan's cost in the pull request means the retention and placement choices are made with the transfer number visible.

What to do next

Know your backup and restore cost before the incident. C3X prices Terraform against a live resource catalog. Start with the quickstart.