Elastic IP Address Limit of Amazon AWS account
Elastic IP Address Limit
By default, all AWS accounts are limited to 5 EIPs, because public (IPv4) Internet addresses are a scarce public resource. We strongly encourage you to use an EIP primarily for load balancing use cases, and use DNS hostnames for all other inter-node communication.
If you feel your architecture warrants additional EIPs, you need to complete the Amazon EC2 Elastic IP Address Request Form to describe your use case.