Step Functions Express, where Standard was overkill.

Standard Step Functions bills per state transition; Express bills per millisecond of execution. For short-running workflows with many transitions, Express is dramatically cheaper. The team had stayed on Standard because that was the default and "it works."

We classified each workflow by duration distribution and state-transition count. Eleven of fourteen fit comfortably inside the Express 5-minute and 25k-transition limits. The remaining three had long-running waits that genuinely needed Standard. CloudWatch Logs replaced the per-execution history view that Express does not provide.

Step Functions bill dropped 62% across the migrated workflows. Workflow duration is unchanged (within the budget). The observability gap closed once teams adapted to querying CloudWatch Logs Insights rather than clicking through the console execution view.