What is the difference between resource-based and spend-based CUDs?

Resource-based CUDs commit to specific Compute Engine resources, such as vCPUs and memory, in one region, and give the deepest discounts. Spend-based CUDs commit to an hourly spend; Compute flexible CUDs apply that spend across regions, projects and machine series in exchange for smaller discounts.

Can you cancel a committed use discount?

No. Google Cloud doesn't let you cancel a commitment after purchase. If you bought one by mistake, you can contact Cloud Billing support within 14 days of the start date, but any change is at Google's discretion.

Do CUDs apply across projects?

Yes, within a Cloud Billing account. Compute flexible CUDs are bought on the billing account and apply across its projects. Resource-based CUDs are bought in a project, and Google now shares them across the billing account's projects by default; unused commitment is still charged to the project that bought it.

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.

In plain English

Think of a yearly contract with a caterer for 100 lunches a day at a lower price per plate. On days only 60 people turn up, you still pay for 100.

Formula and worked example

CUD savings = on-demand value − commitment fee

Commitment fee: = committed resources × CUD price, billed every month of the term
On-demand value: = the resources you used, up to the commitment, × on-demand price

Worked example. Northwind Labs commits to 100 vCPUs, with memory, in one region for a year. At full use that capacity costs $2,200 a month on demand; the commitment costs $1,386 a month, an illustrative 37% discount.
On-demand value of 100 vCPUs for a month	$2,200
Commitment fee for the month	$1,386
Savings at full use	$814
On-demand value if usage drops to 60 vCPUs	$1,320
Savings at 60 vCPUs	−$66

A CUD pays only while usage stays near the commitment. At 60 vCPUs the fee is more than the on-demand price of what ran, which Google Cloud's CUD analysis report shows as negative savings.

Why committed use discounts matter

On Google Cloud, CUDs are the main way to pay less for steady usage. Resource-based CUDs commit to Compute Engine resources such as vCPUs and memory in one region, with discounts Google lists at up to 55% for most machine types and up to 70% for some. Spend-based CUDs commit to an hourly spend instead: Compute flexible CUDs apply it across regions, projects and machine series for Compute Engine, GKE and Cloud Run, at smaller discounts that vary by machine series.

Neither kind can be cancelled after purchase, so the question is the same as on any cloud: how much of today's usage will still be there next year?

Common mistakes

Committing to peak usage. The fee is billed every month of the term, whatever you run. Commit to the baseline you're confident of and leave the rest on demand.
Buying in the wrong region. Resource-based CUDs apply only in the region you buy them in, and their region and type can't be changed afterwards. Moving workloads to another region leaves the commitment with less to cover.
Reading combined reports the wrong way. Google Cloud's CUD analysis doesn't compute utilization when the view combines more than one type of CUD. Check each type on its own.
Changing the shape of usage. Moving workloads to a new machine series or to preemptible VMs can leave a resource-based commitment with less to cover, since it doesn't apply to preemptible VMs.

Where to find it in AWS, Azure and Google Cloud

Where to find Committed use discount by cloud provider
Cloud	What it is called	Where to find it
AWS	Savings Plans and Reserved Instances	AWS's equivalents: Savings Plans commit to an hourly spend, Reserved Instances to a specific instance configuration. See Savings Plan and Reserved Instance.
Azure	Reservations and savings plans	Azure's equivalents: reservations commit to specific resources, and savings plans for compute to an hourly spend.
Google Cloud	Resource-based and spend-based CUDs	Billing → Committed use discounts: buy, track and open CUD analysis for savings, coverage and utilization. Google lists resource-based discounts of up to 55% for most machine types (70% for some); Compute flexible discounts vary by machine series.

How CloudYali helps

CloudYali Financial Commitments shows Google Cloud CUDs next to AWS and Azure commitments, with coverage, utilization, unused commitment and net savings for each, so you can compare commitments across clouds in one view.

See the feature Read how it works in the docs

Commitments & rates
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.
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
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.
Commitments & rates
Sustained use discount (SUD)
A sustained use discount (SUD) is a discount Google Cloud applies automatically to some Compute Engine resources that run for more than 25% of a month. The longer they run, the lower the rate for the remaining hours, up to 30% off for a full month on eligible machine series, with no commitment.

Frequently asked questions

What is the difference between resource-based and spend-based CUDs?
Resource-based CUDs commit to specific Compute Engine resources, such as vCPUs and memory, in one region, and give the deepest discounts. Spend-based CUDs commit to an hourly spend; Compute flexible CUDs apply that spend across regions, projects and machine series in exchange for smaller discounts.
Can you cancel a committed use discount?
No. Google Cloud doesn't let you cancel a commitment after purchase. If you bought one by mistake, you can contact Cloud Billing support within 14 days of the start date, but any change is at Google's discretion.
Do CUDs apply across projects?
Yes, within a Cloud Billing account. Compute flexible CUDs are bought on the billing account and apply across its projects. Resource-based CUDs are bought in a project, and Google now shares them across the billing account's projects by default; unused commitment is still charged to the project that bought it.