LeftSize vs AWS Trusted Advisor and Cost Optimization Hub
AWS has two built-in sources of optimization advice: Trusted Advisor checks and Cost Optimization Hub. LeftSize works alongside them: it scans with read-only access from your own GitHub workflow and turns waste, end-of-support and governance findings into GitHub issues for the team that owns the resources.
Last checked against AWS Trusted Advisor & Cost Optimization Hub's documentation in October 2026.
| LeftSize | AWS Trusted Advisor & Cost Optimization Hub | |
|---|---|---|
| Where findings appear | GitHub issues in the repository you choose, updated on every scan | AWS console and API; Cost Optimization Hub also across accounts in an organization |
| Cost | Free for all 77 cost rules (3 repositories); paid plans from $79/month per GitHub organization | Cost Optimization Hub: no additional charge. Trusted Advisor: all checks need a Business Support+, Enterprise Support or Unified Operations plan; Basic Support gets service limits and selected security and fault tolerance checks |
| Coverage | 97 AWS rules: idle and orphaned resources, 32 end-of-support and retirement rules, security and governance | Rightsizing, idle resources, Savings Plans and Reserved Instances (Cost Optimization Hub); cost, security, fault tolerance, performance and service limit checks (Trusted Advisor) |
| End of support and retirements | Dedicated rules for Lambda runtimes, RDS and ElastiCache Extended Support, EKS versions, Amazon Linux 2 and more, each with dates | Trusted Advisor includes some end-of-support checks, such as Lambda functions on deprecated runtimes (full checks need a paid support plan); Cost Optimization Hub does not cover them |
| Remediation | Steps in the issue, plus @leftsize script for AWS CLI or Terraform | Recommended actions in the console |
| Clouds | AWS and Azure | AWS only |
Where AWS Trusted Advisor & Cost Optimization Hub is the better choice
- Savings Plans and Reserved Instance recommendations that account for your own pricing and discounts.
- Rightsizing based on AWS Compute Optimizer usage data.
- Organization-wide views from the management account, with no setup per repository.
- Service limit and fault tolerance checks, which LeftSize does not cover.
What LeftSize adds
- Findings go to the team that owns the resources, as GitHub issues they can assign, discuss and close.
- 32 end-of-support and retirement rules with dates, so extended support charges and forced upgrades are planned work, not surprises.
- Waste checks without a paid support plan: idle, orphaned and unused resources are covered in the Free plan.
- The same workflow for Azure (91 rules) if you run both clouds.
Using them together
Use Cost Optimization Hub for commitments and rightsizing, and LeftSize to get orphaned resources, end-of-support deadlines and governance gaps in front of the teams who can fix them.