What are the best AWS cost optimization strategies to avoid a massive surprise bill?

All answers to this question.

The first thing you should do is check for "zombie" resources. This includes unattached EBS volumes, idle Load Balancers, and Elastic IPs that aren't associated with an instance. Next, use the AWS Cost Explorer to see exactly which service is driving the cost. If it's EC2, look into "right-sizing"—you might be using a t3.medium when a t3.micro would suffice. Also, set up AWS Budgets immediately with alerts at 50%, 80%, and 100% of your expected spend. This won't lower the bill itself, but it prevents the "surprise" at the end of the month by notifying you early.

   Answered 2025-06-24 by Deborah Young

Have you checked your RDS instances to see if you have "Multi-AZ" enabled? It doubles your cost for redundancy, which you might not need in a dev environment. Are you also using any NAT Gateways, as those have a high hourly charge even if idle?

   Answered 2025-06-25 by Brian Collins

• Brian, that was it! We had Multi-AZ turned on for our development database, which we definitely didn't need yet. We also found a NAT Gateway in a VPC that wasn't even being used. Cutting those two out is going to save us nearly $100 a month already. Thanks for the tip!

     Commented 2025-06-26 by Lisa Crawford

Look into AWS Instance Scheduler. If your dev/test environments don't need to run 24/7, you can set them to shut down at night and on weekends to save up to 60% on those specific instances.

   Answered 2025-06-27 by Steven Morris

• Steven's suggestion is a lifesaver. Most people forget that cloud is pay-as-you-go, and leaving a sandbox environment running over the weekend is just throwing money away. Automation is your best friend here.

     Commented 2025-06-29 by Deborah Young