Which cloud provider has the best reliability and uptime?

There’s no defensible single winner: AWS, Azure, and Google Cloud are all highly reliable, and rankings change depending on the service, region, time period, and measurement method.

For a recent independent snapshot, a tracker updated October 28, 2026 measured AWS and Azure compute services at 100% availability over the prior 30 days, while the Google Cloud Compute Engine regions it tracked measured 99.97–99.98%. That’s only a short window and a limited set of regions—not proof that AWS or Azure is generally more reliable. (uptimeproject.org)

Practical answer: I wouldn’t choose a provider based on a broad uptime ranking. Pick the one that fits your workload and design for failures: use multiple availability zones, backups, health checks, and tested recovery. A provider’s SLA is also not the same as a guarantee that your whole application will stay available; for example, AWS’s EC2 SLA distinguishes single-instance from regional availability. (aws.amazon.com)

If you share the workload and region you care about, I can make a more useful comparison.

There's no clear winner. The big three (AWS, Azure, Google Cloud) are close on paper, and each has had serious outages in 2026. Your own architecture usually matters more than the provider.

Headline uptime numbers are close. One comparison of 2025 figures put Azure at 99.97% uptime with 4 major incidents, and Google Cloud at 99.98% uptime with 3 major incidents. Another source gave AWS 99.95% global uptime in 2025. These are third-party blog figures, not audited data, so treat them as rough.

Recent major incidents (2026):

• AWS: a us-east-1 cooling/thermal failure in May 2026 lasted about 28 hours. One tracker notes that 9 of AWS's 14 major outages hit us-east-1, its oldest and largest region.
• Azure: Azure West US 2 had a 22-hour power and cooling outage in May, and a power-safety event in January caused a multi-hour outage across several services.
• Google Cloud: a power-feed voltage drop in July tripped breakers at a Netherlands facility, and an August us-west1 outage lasted about two hours and 22 minutes after fiber maintenance went wrong.

One analysis concluded that none of the three has a clean reliability record over this period.

SLAs and remedies:

• AWS offers a 99.99% region-level SLA for EC2 instances spread across multiple Availability Zones.
• Azure promotes a 99.99% monthly uptime SLA for zone-redundant virtual machines.
• Service credits differ: one comparison says AWS's SLA credit tops out at 30% of a monthly service fee, Azure's can reach 100% for its worst-affected services, and Google Cloud caps out around 50% for Compute Engine.

Trade-offs: Commentators describe different weak spots. AWS has had control-plane problems and a regional bottleneck in us-east-1. Azure's recoveries have tended to take longer. Google has had fewer incidents, but a smaller service catalog means fewer redundancy options.

Practical takeaway: Any provider can go down, so the best uptime comes from design. Spread workloads across multiple availability zones, and across regions for critical systems. Choose the provider whose services, region locations, and compliance certifications fit your needs, then test failover. If you tell me your workload type, region, and budget, I can give a more specific recommendation.

There is no single "best" cloud provider for reliability and uptime. All three major hyperscalers—Amazon Web Services (AWS), Microsoft Azure, and Google Cloud Platform (GCP)—are considered industry leaders that offer robust, enterprise-grade infrastructure with extremely high availability.

Rather than one provider being objectively superior, their reliability often depends on how you architect your applications and which specific services or regions you utilize.

How They Compare

• AWS: As the most mature platform with the largest global infrastructure, AWS is frequently cited as the standard for reliability. It features a vast number of Availability Zones (AZs) designed for high fault tolerance. However, its sheer scale and complexity mean that when incidents do occur, they can be high-profile.
• Microsoft Azure: Azure is highly reliable and a preferred choice for organizations deeply integrated into the Microsoft ecosystem. It often performs very well in hybrid cloud environments.
• Google Cloud (GCP): GCP is often recognized for high-performance infrastructure and a strong, private global network backbone. It is frequently praised for its data analytics and Kubernetes (GKE) capabilities.

Key Realities of Cloud Reliability

When evaluating these providers, keep these critical factors in mind:

1. SLA vs. Reality: While all providers offer Service Level Agreements (SLAs) promising "four nines" (99.99%) or similar uptime, these are financial guarantees rather than absolute predictions of performance. Outages occur across all platforms.
2. Regional Performance: Reliability is not uniform across all data centers. Some regions may experience more instability than others due to age, load, or local infrastructure issues. Always check the status history of the specific region you plan to use.
3. Architecture Matters Most: The "uptime" you experience is more dependent on your own architectural choices than the provider itself. Building for reliability requires:
   • Multi-AZ Deployment: Distributing workloads across physically separate availability zones to survive local failures.
   • Multi-Region Strategy: For mission-critical applications, deploying across different geographic regions ensures you stay online even if an entire region goes down.
   • Observability: Implementing robust monitoring so your team can detect and mitigate issues before they impact your users.

Summary Recommendation

If you are choosing between the "Big Three," the decision should generally be driven by your existing technology stack, team expertise, and specific workload requirements rather than uptime statistics. All three are capable of providing the reliability needed for almost any business-critical application if architected correctly.

There isn’t a clear, universal winner. AWS, Azure, and Google Cloud can all provide high availability, and the reliability of your specific service and architecture matters more than the provider name.

In one comparison of major public incidents from 2017–2025, Google Cloud had the shortest median recovery time—about 2 hours 48 minutes, versus 3 hours 37 minutes for AWS and 3 hours 46 minutes for Azure. That’s a useful signal, but it doesn’t prove Google is the most reliable overall: incident counts and durations depend on what gets disclosed and how incidents are measured. ²¹⁰

For a concrete service-level comparison, AWS’s EC2 SLA promises 99.99% monthly availability when instances are deployed across at least two Availability Zones. ¹² SLAs are service- and deployment-specific, so compare the exact products and architecture you plan to use rather than relying on a provider-wide uptime figure.

Practical takeaway: choose based on your workload and team’s expertise, then design for failure—use multiple zones, backups, health checks, and tested recovery procedures. A well-designed deployment on any of the three can be more reliable than a single-region setup on the provider with the best headline metric. ⁵