How to fix HPA: scale down disabled by policy or stabilization window in Kubernetes

KubernetesINTERMEDIATEHIGH

HorizontalPodAutoscaler will not scale down pods even when demand decreases. Scale-down is disabled by policy, stabilization window, or autoscaling config.

What this error means

HPA can scale up quickly but intentionally limits scale-down to prevent thrashing (rapid up/down cycles that waste resources). The scale-down behavior is controlled by stabilization windows and scale-down policies. When these are too conservative, HPA will not scale down even when metrics indicate fewer replicas are needed.

Typical symptoms

Pod count stays high even after load decreases
HPA will not scale down to minReplicas
kubectl describe hpa shows scale-down behavior disabled
Metrics show low usage but pod count unchanged
HPA events: "scale down stabilization active"
Resource utilization low but cluster remains full
Unnecessary pods consuming cluster resources

Common causes

Scale-down stabilization window too long (default 5 minutes)
Scale-down policy explicitly disabled
Auto-scaler behavior policy set to conservative
Recent scale-up event still within stabilization window
Pod disruption budget preventing voluntary eviction
minReplicas set too high
Scaling policy with very slow scale-down rate

How to fix "HPA: scale down disabled by policy or stabilization window"

1Step 1

First diagnostic step

2Step 2

Second diagnostic step

3Step 3

Third diagnostic step

4Step 4

Fourth diagnostic step

Step 5

Advanced notes

Additional notes and platform-specific considerations.

Related errors

Official resources & further reading

📚Kubernetes Official Documentation
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Kubernetes API Reference(Official Docs)
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Kubernetes Tasks: Run Applications(Official Docs)
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Stack Overflow: Kubernetes hpa scale down disabled(Stack Overflow)
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Kubernetes GitHub Issues(GitHub)