A 900 TB estate has to move from one cloud to another. At list egress rates the transfer alone is quoted near $0.08 per GB and the finance director refuses. Since 2024 the largest providers waive transfer charges for customers leaving. Sequence the move and say where the waiver does not apply.

What is actually being asked

Not "how do we get free egress". The transfer line is the smallest of the three costs in this project, and a migration plan built around claiming a waiver will spend the waiver's clock on work that should have happened before it started.

The policy facts, which carry dates because they change: Google Cloud announced on 11 January 2024 that customers leaving for another provider or for on-premises could transfer their data out without network transfer charges, and AWS followed on 5 March 2024. As reported at launch, both require a request and approval, both give 60 days after approval to complete the exit, Google's applied to customers moving their entire workload off its platform, and AWS issued credits for the migrated data without requiring the account to be closed. The driver was the switching provisions of the EU Data Act. Confirm current terms with the provider before planning around them.

The sequence

1. Inventory by billed boundary, not by dataset. Tag every flow as leaving the provider, crossing regions, or crossing zones. Only the first is in scope for a waiver.
2. Shrink the payload before anyone signs anything. Expire noncurrent object versions, drop derived data you can recompute on the far side, compact small objects. 900 TB is frequently 600 TB of data and 300 TB of history nobody would pay to move.
3. Build and validate the target with a few terabytes of paid transfer. At list price a 3 TB rehearsal costs about $240 and is the cheapest insurance in the plan.
4. Then request the waiver, because approval starts the 60-day clock and that clock should only ever cover bulk movement.
5. Move cold bulk first, by physical transfer appliance if the clock is tight, then the working set, then repoint reads. Each step is reversible by repointing reads back.
6. Cut over writes last. This is the point of no return: after it, rolling back means moving data out of the new provider at full price with no waiver, since you used yours.

Where the waiver does not apply

Steady-state multi-cloud traffic, cross-region and cross-zone transfer inside a provider, CDN delivery to end users, and any hybrid flow you intend to keep. It covers a one-time exit, verified by the provider as not being a normal part of your business. It also does not touch the two costs that dominate: the engineering months, and the dual-run overlap where both platforms are paid at once. Three months of overlap on a $120000-a-month platform is $360000, roughly five times the $73000 transfer bill at list rates that started the argument.

When this is the wrong answer

If the destination is chosen for price alone, run the arithmetic on the whole five-year model first: a migration that saves 15% of run rate and costs 18 engineer-months plus a quarter of dual-run does not pay back inside the planning horizon. And if the data is only 900 TB of object storage with no compute attached, consider whether it needs to move at all, since reading it across providers may be cheaper than relocating the estate it belongs to.