I have developed several services and they are deployed into two AWS accounts.

Access is only allowed from company's source IP. But the services has to communicate to each other. I am not allowed to use VPC pairing. Are there any other options I can use to whiteliste the AWS accounts each other in security groups?

CodePudding user response：

You can explore the option of peering cross account VPCs.
VPC endpoint service (PrivateLink) cross-account access : A VPC endpoint is a connection from your VPC to a specific service provided by AWS or by someone else. The VPC endpoint is exposed as a private IP address within your VPC, accessible using a private DNS name.

CodePudding user response：

Is the two accounts in the same Organization ? if yes you can share your VPC with AWS RAM (that means you can deploy your infra in the same VPC) but from different accounts ==> https://aws.amazon.com/blogs/networking-and-content-delivery/vpc-sharing-a-new-approach-to-multiple-accounts-and-vpc-management/

Also you can check creating a network load balancer in your service VPC exposed with a VPC endpoint service to your VPC client.