Each customer master key (CMK) that you create in AWS Key Management Service, regardless of whether you use it with KMS-generated key material or key material imported by you, costs $1/month until you delete it. For a CMK with key material generated by KMS, if you opt-in to have the CMK automatically rotated each year, each newly rotated version will raise the cost of the CMK by $1/month. AWS KMS retains and manages each previous version of the CMK to ensure you can decrypt older data. You are not charged for the following:

  • AWS-managed CMKs, which are automatically created on your behalf when you first attempt to encrypt a resource in a supported AWS service.
  • CMKs that are scheduled for deletion. If you cancel the deletion during the waiting period, the CMK will incur charges as though it was never scheduled for deletion.
  • Data keys, which are created by GenerateDataKey and GenerateDataKeyWithoutPlaintext API requests. You are charged for these API requests per the Usage pricing discussed below whether you make these API requests directly or they are made on your behalf by an integrated AWS service. You are not charged an ongoing monthly fee for the data keys themselves as they are neither stored nor managed by AWS KMS.

Try AWS Key Management Service

AWS Free Tier includes 20,000 free AWS Key Management Service requests each month.

View AWS Free Tier Details »


Each API request of AWS Key Management Service (outside of the free tier) costs:

$0.03 per 10,000 requests in US East (N. Virginia), US East (Ohio), US West (Oregon), US West (Northern California), Canada (Central), EU (Ireland), EU (Frankfurt), EU (London), EU (Paris), Asia Pacific (Singapore), Asia Pacific (Tokyo), Asia Pacific (Osaka-Local), Asia Pacific (Sydney), Asia Pacific (Seoul), Asia Pacific (Mumbai), South America (Sao Paulo)

$0.04 per 10,000 requests in AWS GovCloud (US)

Free Tier

AWS Key Management Service provides a free tier containing the following:

20,000 requests/month calculated across all the following regions-

US East (N. Virginia), US East (Ohio), US West (Oregon), US West (Northern California), Canada (Central), EU (Ireland), EU (Frankfurt), EU (London), EU (Paris), Asia Pacific (Singapore), Asia Pacific (Tokyo), Asia Pacific (Osaka-Local), Asia Pacific (Sydney), Asia Pacific (Seoul), Asia Pacific (Mumbai), South America (Sao Paulo)

20,000 requests/month in AWS GovCloud (US)

Pricing examples

Amazon EBS Example

1 CMK used as a master key when creating 250 encrypted EBS volumes per month via the AWS KMS CLI or APIs.

Cost Dimensions:

  • 1 CMK
  • 3 X 250 API requests to create and provision a unique data encryption key for each of 250 volumes
Monthly cost:
$1.00 1 CMK
$0.00 0 requests (750 requests - 20,000 free tier requests)
Amazon S3 Example

1 CMK used to encrypt 10,000 unique files that are collectively decrypted for access 2,000,000 times per month.

Cost Dimensions:

  • 1 CMK
  • 10,000 Encrypt requests (1 x 10,000 objects)
  • 2,000,000 Decrypt requests to access the objects

Monthly Cost:

$1.00 1 CMK
$5.97 1,990,000 requests (2,010,000 requests - 20,000 free tier requests) x $0.03 / 10,000 requests

AWS CloudTrail logging

If you enable AWS CloudTrail on your account, you can obtain logs of API calls made to or by AWS KMS. There is no additional charge for AWS CloudTrail, but standard rates for Amazon S3 and Amazon SNS usage apply. Please see the AWS CloudTrail pricing page for more information.

Additional pricing resources

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