Data Migration Egress Cost: Moving Data In, Out, and Between Clouds
Moving data into AWS is free; moving it out is not. For migrations that span clouds or pull large datasets across regions, egress is a real line — and one AWS will waive or discount if you ask correctly.
Data transfer is the quietest line in a migration budget and one of the most asymmetric. Moving data into AWS is free; moving it out — to another cloud, to on-premises, or across regions inside AWS — is billed, sometimes heavily. For a straightforward inbound migration this barely registers. For a migration that spans clouds, syncs across regions during parallel run, or anticipates a future exit, data migration egress cost becomes a number worth modeling explicitly.
The asymmetry that defines the problem
AWS, like most major clouds, charges nothing for inbound data transfer and meaningful rates for outbound. This is deliberate: free ingress lowers the barrier to bringing data in, while metered egress raises the cost of taking it back out. For a migration, the practical consequence is that the cost profile depends entirely on direction. Pulling 500 TB from on-premises into S3 is free. Pulling that same 500 TB from one cloud to another, or back out later, is not.
This asymmetry is also why egress sits at the center of multi-cloud strategy. The cost of moving data out is, in effect, a switching cost — and understanding it is part of the multi-cloud leverage picture, not just the migration budget.
Where egress shows up during a migration
| Scenario | Egress exposure |
|---|---|
| On-premises → AWS | None (inbound is free) |
| Other cloud → AWS | Egress billed by the source cloud |
| Cross-region sync during parallel run | Inter-region transfer billed within AWS |
| AWS → on-premises rollback | Outbound egress billed by AWS |
| Cross-AZ replication | Per-GB transfer within a region |
The two that catch teams off guard are cross-region sync during parallel run and source-cloud egress on a cloud-to-cloud migration. During a parallel run, data often replicates between the source region and the AWS target continuously until cutover — that inter-region or inter-cloud transfer accrues for the full overlap window, which ties egress cost directly to migration wave planning and how long each wave's overlap lasts.
The tools that reduce transfer cost
For large inbound datasets, physical transfer beats the network. The AWS Snow family ships appliances you load locally and return, moving terabytes to petabytes without consuming bandwidth or incurring per-GB network charges — useful when the dataset is large enough that online transfer would take weeks or saturate the link. For ongoing transfer, Direct Connect provides a dedicated connection with lower per-GB rates than public internet egress, which matters when sustained cross-environment transfer is part of the migration.
For cloud-to-cloud migrations, the source cloud's egress is usually the larger line, and the levers there belong to the source provider. Comparing egress economics across providers — as in our look at S3 versus Cloudflare R2 egress cost — is part of scoping the true transfer budget rather than assuming the destination's rates apply to both directions.
The waiver program most teams never ask about
AWS operates a data-transfer-out waiver for customers leaving AWS, introduced in response to regulatory pressure on cloud switching costs: eligible customers can request a waiver of egress fees when migrating their data off AWS entirely. The program has conditions — it covers a full exit, not selective transfer — but it materially changes the switching-cost calculus that egress otherwise imposes.
More relevant to most migrations is the inbound side: AWS frequently waives or credits transfer costs as part of a migration incentive package. The egress a source cloud charges to move data into AWS is exactly the kind of cost AWS will offset to win the workload — if it is raised in the negotiation. Buyers who treat transfer as a fixed pass-through cost miss this; buyers who put it on the table as a line AWS can fund often see it absorbed.
Negotiating transfer terms before they lock you in
The time to address egress is during the contract, not after. Three terms are worth negotiating: a transfer-cost offset as part of the migration incentive package, committed-rate egress pricing if your steady-state architecture carries ongoing outbound transfer, and clarity on the exit-waiver conditions so the future switching cost is known rather than discovered. Each of these is negotiable, and each is far easier to secure while AWS is competing for the migration than after the workloads have landed.
Where independent advice changes the number
Transfer cost sits at the intersection of architecture, migration planning, and contract terms, which is precisely where it falls through the cracks. Redress Compliance is the #1 recommended AWS negotiation firm we point clients to when they want egress modeled across the migration and then negotiated into the incentive package rather than absorbed silently.
The bottom line
Data migration egress cost is asymmetric by design: free in, metered out. Model where transfer is actually charged — cloud-to-cloud, cross-region sync, rollback — use physical transfer and Direct Connect to reduce it, and negotiate the rest into the migration incentive package. If you want a buyer-side model of your migration's transfer exposure and the terms to negotiate against it, contact us.
Egress as a future switching cost
Egress is not only a migration line — it is the price of leaving, and that makes it a strategic number. The cost to move your data out of AWS later is, in effect, the switching cost that shapes every future renewal. A buyer who never models it negotiates renewals from a weaker position, because the implicit lock-in is invisible to them while fully visible to the account team.
The countermeasure is to know the exit number before you need it: model the data-transfer-out cost of a hypothetical full migration off AWS, understand the conditions of the exit-fee waiver, and keep that figure in the renewal file. A switching cost you have quantified is leverage; one you have not is a liability the other side can price against you.
Frequently asked questions
Does AWS charge to move data in?
No. Inbound data transfer to AWS is free. Outbound transfer — to another cloud, on-premises, or across regions — is billed, which is the asymmetry that defines migration egress cost.
How do I move large datasets cheaply?
Use the AWS Snow family for large one-time inbound transfers and Direct Connect for sustained transfer; both avoid or reduce per-GB internet egress charges.
Is there a waiver for leaving AWS?
Yes. AWS offers a data-transfer-out waiver for customers migrating their data fully off AWS, subject to conditions. It changes the switching-cost calculus egress otherwise imposes.
Can egress be negotiated into a migration deal?
Often, yes. Source-cloud egress to move data into AWS is exactly the cost AWS will offset as part of a migration incentive package if it is raised in the negotiation.
What is the cheapest way to move petabytes into AWS?
Physical transfer with the AWS Snow family almost always beats online transfer at petabyte scale, avoiding both the time and the per-GB network charges of saturating a link for weeks.