Unassociated Elastic IP Address

Jason Eckle

Service Category

Networking

Cloud Provider

AWS

Service Name

AWS EIP

Inefficiency Type

Unused Resource

Explanation

Elastic IPs are often provisioned but forgotten — left unassociated, or still attached to EC2 instances that have been stopped. In either case, AWS treats the EIP as idle and applies an hourly charge. Although the cost per hour is relatively small, these charges accumulate quietly, especially across environments with frequent provisioning, decommissioning, or ephemeral workloads. Many organizations overlook the fact that even a single EIP attached to a stopped instance is billable. Without periodic review, this creates persistent, low-visibility waste across AWS accounts.

Relevant Billing Model

Elastic IPs are billed under the following rules:

Free: One Elastic IP actively associated with a running EC2 instance
Billed hourly:
If the EIP is unassociated (not linked to any resource)
If the EIP is associated with a stopped EC2 instance
If there is more than one EIP per instance

This pricing model is designed to discourage allocation of static IP addresses that are not in active use.

Detection

List all Elastic IPs and identify those that:

Are not associated with any resource
Are associated with an EC2 instance that is currently stopped
Are secondary EIPs beyond the first on any instance
Use tags or resource metadata to validate whether these EIPs are still required for future use

Remediation

Release any EIPs that are no longer required
Automate audits to identify unassociated or inactive EIPs on a recurring basis
Update IaC templates or provisioning workflows to clean up networking assets during teardown

Relevant Documentation