CostLensUnder-Utilized Reservation (Azure)
Under-Utilized Reservation (Azure)
CostLens flags Azure reservations running below their utilization target, where the unused commitment is wasted spend.
Updated July 20261 min read
CostLens flags under-utilized Azure reservations — reservations running below their utilization target. A reservation you're not fully using is money already committed but not saving anything.
Advisory only
You can't "delete" the waste on a reservation you've already bought — the value is in re-scoping, exchanging, or right-sizing your next purchase. CostLens surfaces the low utilization so you can act.
How it works
Reservation summaries are read
CostLens reads Azure Consumption reservation summaries (reserved vs used hours, average utilization).
Under-used reservations are flagged
Reservations averaging below ~75% utilization are surfaced, with a coarse estimate of the wasted committed hours.
What to do
- Review why utilization is low — the covered resources may have been resized, moved, or deleted.
- Exchange the reservation for a better-fitting SKU/scope, or adjust the quantity, in the Azure portal (Reservations → Exchange/Refund).
- Right-size future reservation purchases to your actual steady-state.
Severity levels
| Severity | Estimated monthly savings |
|---|---|
| critical | >$500 |
| high | $100–$500 |
| medium | $20–$100 |
| low | <$20 |
Required permissions
- Detect:
Cost Management Reader(reservation summaries) — see Azure Accounts.
Limitations
- The wasted-cost figure is a coarse estimate — the exact reservation price isn't in the summary.
- Utilization data is reservation-order-scoped and may not surface in every tenant; the check degrades to nothing when unavailable.