In some cases we couldn't use public ip address not even an elastic ip for your ec2 instance , for example PCI audit related situations. But you should give internet access to your ec2 app servers to sent notification or alert mails to outside. In that case you can use the NAT Gateway for doing this. 1. First Create a NAT gateway in VPC section. While creating the NAT Gateway, you should give the subnet as the Public Subnet having route table target as an "Internet Gateway". 2. Now edit your route table associated with your private EC2's subnet and make the target as "Nat gateway ID" That is all , now you will get internet access to your private EC2 instance, without public ip or elastic ip and having only Private ip in the instance description session.