Savings Plan (SP)
A Savings Plan is an AWS or Azure commitment to spend a fixed amount per hour on eligible compute for one or three years. Usage up to that amount is billed at lower rates, and the discount follows your usage across instance sizes and, with the most flexible plans, instance families and regions.
In plain English
Think of a dining plan at a food court. You commit to spend a fixed amount every month, and in return every meal costs less, at whichever stall you choose. Switch stalls as often as you like; the commitment stays the same, and what you don't spend is gone.
Formula and worked example
Savings Plan savings = covered usage at on-demand prices − commitment paid
- Commitment paid
- = hourly commitment × hours in the period, used or not
- Covered usage at on-demand prices
- = what the usage the plan paid for would have cost without it
| Hourly commitment | $82.19 |
|---|---|
| Hours in the month | 730 |
| Commitment paid for the month (rounded) | $60,000 |
| Usage the plan covered, at Savings Plan rates | $57,000 |
| The same usage at on-demand prices | $76,000 |
| Savings from the plan | $16,000 |
The plan saves $16,000 even though $3,000 of the commitment went unused. Commit more than the steady baseline and the unused part eats into the saving; usage above the commitment is simply billed at on-demand rates.
Why Savings Plans matter
Savings Plans are the most flexible way to commit on AWS and Azure. Because the discount follows your usage rather than a specific machine, you can change instance sizes and, with the most flexible plans, instance families and regions without losing it. For EC2, AWS now recommends Savings Plans over Reserved Instances.
The trade-off is that the commitment is money per hour, not machines. Each hour, usage up to the commitment gets the lower rate; anything above it is billed on demand, and any part of the commitment that hour doesn't use is lost.
Common mistakes
- Committing to the average instead of the floor. The plan bills the full commitment every hour. Size it to the usage you're confident will still be there at night, at weekends and after the next optimization, not to the monthly average.
- Forgetting the commitment is in discounted dollars. A $60,000 monthly commitment at rates 25% below on-demand covers about $80,000 of usage at on-demand prices, not $60,000. Convert on-demand usage at the plan's rates before you size it.
- Picking the wrong plan type. On AWS, EC2 Instance Savings Plans give up to 72% off but only for one instance family in one region; Compute Savings Plans give up to 66% and follow your usage across families, regions, Fargate and Lambda. Choose by how much your architecture is still changing.
- Buying without checking existing reservations. AWS applies EC2 Reserved Instances before Savings Plans, and Azure applies reservations first too, so a new plan can end up covering less usage than its recommendation assumed.
Where to find it in AWS, Azure and Google Cloud
| Cloud | What it is called | Where to find it |
|---|---|---|
 AWS | Savings Plans (Compute, EC2 Instance, Database, SageMaker AI) | Billing and Cost Management → Savings Plans: recommendations, purchase, inventory, and coverage and utilization reports. Commitments are dollars per hour for one or three years, with no, partial or all upfront payment. |
 Azure | Azure savings plan for compute | Bought and managed under Savings plans in the Azure portal: a one- or three-year hourly commitment, up to 65% off pay-as-you-go prices, for services such as Virtual Machines, App Service and Container Instances. Scope it to a resource group, subscription, management group or the whole billing account. |
 Google Cloud | Compute flexible CUDs | Google Cloud's closest equivalent: a spend-based commitment that applies across regions, projects and machine series for Compute Engine, GKE and Cloud Run. See committed use discount. |
How CloudYali helps
CloudYali Financial Commitments lists every AWS Savings Plan and Azure savings plan with its coverage, utilization, unused commitment and net savings, so you can see whether each plan is the right size before it renews.
Related terms
Commitments & rates
Reserved Instance (RI)
A Reserved Instance (RI) is a one- or three-year commitment to a specific kind of capacity, such as an EC2 instance type in a region or an RDS database, in exchange for a lower hourly price. It's a billing discount, not a server, and you pay for every hour of the term whether the capacity runs or not.
Commitments & rates
Committed use discount (CUD)
A committed use discount (CUD) is Google Cloud's commitment discount: you commit to a set amount of resources, such as vCPUs and memory in one region, or to an hourly spend, for one or three years, and pay lower prices on that usage. The commitment is billed every month of the term, used or not.
Commitments & rates
Commitment coverage
Commitment coverage is the share of commitment-eligible usage that a Reserved Instance, Savings Plan, Azure reservation or Google Cloud committed use discount paid for, measured at on-demand prices. The rest was billed at full on-demand rates, so low coverage on steady usage is money left on the table.
Commitments & rates
Commitment utilization
Commitment utilization is the share of a commitment you paid for that your usage actually consumed: used commitment ÷ total commitment. Anything below 100% is commitment you paid for and didn't use, so it shows how well a Reserved Instance, Savings Plan, Azure reservation or committed use discount fits real usage.
Commitments & rates
Effective savings rate (ESR)
Effective savings rate (ESR) is net savings as a share of what all commitment-eligible usage would have cost at on-demand prices. Because it subtracts commitment you paid for but didn't use, it is the one rate-optimization number that buying too many Reserved Instances, Savings Plans or committed use discounts can't inflate.
Billing & cost types
On-demand price
On-demand price is the public, pay-as-you-go price for cloud usage with no commitment: you pay per second, hour, gigabyte or request for what you use. It is the baseline that every commitment discount, and metrics such as coverage and effective savings rate, are measured against.
Frequently asked questions
Savings Plans or Reserved Instances: which should you buy?
For EC2, AWS recommends Savings Plans: similar discounts with far more flexibility. Reserved Instances still make sense for services Savings Plans don't cover, and zonal EC2 Reserved Instances reserve capacity in an Availability Zone, which Savings Plans don't.
What happens when usage goes above the commitment?
The extra usage is billed at on-demand rates. That is by design: a Savings Plan should cover your steady baseline, with the peaks paid on demand.
Does a Savings Plan cover other accounts?
On AWS, a plan applies to usage in other accounts of the organization when discount sharing is turned on, after the owning account's usage. Azure savings plans have a scope: a resource group, a subscription, a management group or the whole billing account (shared).
