In roughly two thirds of the estates reviewed, the deeper rate was applied to workloads that later changed family or moved region, stranding 15 to 25 percent of the commitment
On EC2 compute the deepest rate only beats the flexible one if the workload never moves. Lock the rate to permanence, not to optimism.
Prepared by Redress Compliance · August 19, 2026 · AWS compute commitment reviews led. 25 to 35 files, 2024 to 2025.
Executive summary
Stranded commitment ran 15 to 25 percent. That share of EC2 Instance commitment was tied to families the estate later migrated off, across roughly 25 to 35 compute commitment reviews led between 2024 and 2025.
Region lock surprised buyers. Workloads moved region for latency or cost, leaving the commitment in the original region idle and earning nothing.
The wrong tool was used for capacity. Capacity sensitive workloads used Savings Plans where a Reserved Instance reservation was actually needed.
The flexible Compute plan would have kept the discount through the change, which is the whole argument against defaulting to the deeper rate.
How do EC2 Instance Savings Plans work?
An EC2 Instance Savings Plan commits you to a steady hourly spend on a particular instance family within one region, for a one or three year term. In exchange you get the deepest Savings Plan rate available.
The plan is documented on the compute Savings Plans pricing page.
The rate beats the flexible Compute plan, but the discount only applies inside the chosen family and region. Move the workload and the commitment can sit idle.
What the plan locks and what it does not
The family and region are fixed for the term. Instance size is not, so you keep size flexibility within the family, as set out in the Savings Plans user guide.
- Locked: instance family and region for the full term.
- Flexible: instance size within the family, and operating system.
- Idle risk: commitment outside the locked family or region earns no discount.
| Attribute | Status | Effect | Buyer action |
|---|---|---|---|
| Instance family | Locked | Deepest rate within family | Pick stable families only |
| Region | Locked | No discount if workload moves | Confirm region permanence |
| Instance size | Flexible | Move sizes freely | Right size without penalty |
Three year all upfront gives the deepest rate, as with all Savings Plans. The general model sits on the EC2 pricing page.
How do the three tools compare?
They overlap but solve different problems. Compute Savings Plans trade rate for flexibility, EC2 Instance plans trade flexibility for rate, and Reserved Instances add a capacity reservation.
Choosing wrongly is the most common and expensive mistake, because each tool is right only for a specific workload profile.
Against Compute Savings Plans
- Rate: EC2 Instance plans discount more deeply within the locked family.
- Flexibility: Compute plans cover any family, region, and serverless compute.
- Fit: EC2 Instance for stable known workloads, Compute for change.
Against Reserved Instances
Reserved Instances can guarantee capacity in a specific Availability Zone, which Savings Plans do not. Where a capacity reservation matters, the Reserved Instances model is still the right tool.
Confirming a workload will stay on its family and region for the full term is the test that decides whether the deeper EC2 rate pays off.
- Commit sizing from real usage data, with the same workload priced across clouds
- Savings by workstream with a phased plan you can actually execute
- Invoice lines matched daily against what the contract says you owe
How do you manage the family and region lock?
The lock is only a risk if the workload moves. The discipline is to apply EC2 Instance plans only to workloads with a confirmed, stable family and region for the full term.
Three tests before you commit
- Confirm permanence: apply the plan only where the family and region are settled.
- Reserve flexibility: keep migrating workloads on Compute plans instead.
- Plan the term: match term length to how long the workload will stay put.
The work is workload classification. Bring a stability and roadmap view of each workload, family by family, and the lever is matching the tool to the profile.
The wider approach sits in negotiating with AWS.
The AWS Savings Plans recommendations
The classification test, the term matching, and the ten buyer side moves before you commit.
Get the brief →What 25 to 35 commitment reviews showed
Across the AWS compute commitment reviews led between 2024 and 2025, the recurring finding was that the deeper EC2 Instance rate was applied to workloads that did not stay put.
The three patterns that recurred
- Stranded commitment: 15 to 25 percent of EC2 Instance commitment was tied to families the estate later migrated off.
- Region lock surprise: workloads moved region for latency or cost, leaving commitment in the original region idle.
- Wrong tool: capacity sensitive workloads used Savings Plans where a Reserved Instance reservation was actually needed.
None of the three is a pricing failure. All three are classification failures made before any rate was agreed.
Research briefingAWS negotiations, episode threeWhere commitment instruments, workload permanence and the discount curve meet inside a compute estate.
Where the common advice on EC2 Instance plans is wrong
The standard advice is to always choose the EC2 Instance plan over the Compute plan because it gives a deeper discount. We disagree.
In roughly two thirds of the estates reviewed in 2024 and 2025, the deeper rate was applied to workloads that later changed family or moved region, stranding 15 to 25 percent of the commitment.
Reserve EC2 Instance plans for workloads with confirmed family and region permanence, and default everything migrating or uncertain to Compute plans.
The deeper rate is only deeper if the commitment is actually used. Lock the rate to permanence, not to optimism.
Tied to families the estate later migrated away from.
The middle of the distribution, not the worst case.
Against the deeper headline rate the plan advertised.
Your first five moves
- Classify every workload by family and region permanence before choosing any commitment instrument.
- Apply EC2 Instance plans only where the family and region are settled for the full term, not where they are expected to settle.
- Default everything migrating or uncertain to Compute plans, because the flexible rate survives the change.
- Use Reserved Instances where a capacity reservation is the actual requirement, since Savings Plans do not provide one.
- Match term length to how long the workload will genuinely stay put, rather than to the term that shows the deepest headline rate.
Frequently asked questions
What does an EC2 Instance Savings Plan commit you to?
A steady hourly spend on a particular instance family within one region, for a one or three year term, in exchange for the deepest Savings Plan rate.
What exactly is locked?
The instance family and the region, for the full term. Instance size stays flexible within the family, along with operating system.
How much commitment gets stranded?
Between 15 and 25 percent, tied to families the estate later migrated off. The median across the file was 20 percent.
Should you always take the deeper rate?
No. In roughly two thirds of estates reviewed, the deeper rate went to workloads that later changed family or moved region.
What happens when a workload moves region?
The commitment stays in the original region and earns no discount. It sits idle for the remainder of the term.
When is a Compute Savings Plan better?
Whenever the workload is migrating or uncertain. The flexible plan keeps the discount through a family or region change.
When do you still need Reserved Instances?
Where a capacity reservation matters. Reserved Instances can guarantee capacity in a specific Availability Zone, which Savings Plans do not.
What is the test before committing?
Whether the workload will stay on its family and region for the full term. That single question decides whether the deeper rate pays off.
Does size flexibility survive the lock?
Yes. You can move between sizes within the locked family without losing the rate, so right sizing carries no penalty.
What term gives the deepest rate?
Three year all upfront, as with all Savings Plans. Match that term to real workload permanence rather than to the discount curve.