Cheat sheetAWS-06

Cost Optimization

AWS SAA / Cost Optimization

Pick the cheapest option that still meets the requirement by matching pricing models and tiering to the workload.

OD
On-DemandPay-per-use, no commitment — spiky or short-lived workloads.
RI/SP
Reserved / SavingsCommit 1–3 yrs for big discounts on steady usage.
Spot
Spot InstancesUp to ~90% off spare capacity; interruptible batch work only.
Tier
S3 tieringLifecycle + Intelligent-Tiering move cold data to cheaper classes.
⚑

Reserved/Savings for the always-on tier; Spot for interruptible jobs; right-size the rest.

24/7 databaseReserved Instances or a Savings Plan for the largest steady-state discount.
Nightly batchSpot Instances at up to ~90% off; a reclaim simply reschedules the job.
Steady = Reserved/Savings Plan; spiky = On-Demand
Interruptible = Spot (2-min reclaim notice)
Cost Explorer + Budgets for visibility and alerts
pricingreservedspotsavings-plansright-sizingcost-explorer
review in 6d