Cloud Reliability Comparison
AWS vs Azure vs GCP: Outage Frequency & History Compared
Updated July 2026 · 26 documented major incidents across three clouds
Outage Frequency, In Brief
By documented major incidents, the three hyperscalers cluster around one to two significant outages per year each. Our database records 9 major AWS incidents since 2012, 9 for Azure since 2018, and 7 for GCP since 2016. Raw counts are not a clean reliability ranking - they reflect how long each provider has been tracked and how visible each event was. AWS outages concentrate in us-east-1 and affect the most customers per event; Azure incidents often hit Microsoft 365 and Teams; GCP fails less often but its global control plane lets a single failure scale worldwide within minutes (June 2025). Full side-by-side table, combined timeline, and SLA credit comparison below.
Outage Frequency & History, Side by Side
| Metric | AWS | Azure | GCP |
|---|---|---|---|
| Documented major incidents | 9 | 9 | 7 |
| Tracking window | since 2012 | since 2018 | since 2016 |
| Approx. frequency | ~1 / yr | ~1-2 / yr | ~1 / yr |
| Costliest incident | Dec 2021 + S3 Feb 2017, $150M+ each | Oct 2025 Front Door global outage (~8.5h) | Jun 2025 Service Control / IAM (dozens of products) |
| Most recent major | Jul 2026 CloudFront VPC Origins failure (~3.5h, global) | Feb 2026 multi-region control-plane failure (~12h) | Jun 2025 IAM auth failure (~3h, us-central1 ~7h) |
| SLA credit range | 10% -> 30% (EC2, <99%) | 25% -> 100% (<99%) | 10% -> 50% (Compute, <95%) |
| Failure pattern | Concentrated in us-east-1; affects the most customers per event | Often hits Microsoft 365 and Teams - high enterprise visibility | Rarer, but a global control plane means failures scale worldwide fast |
Incident counts are the major outages documented on each provider page below; they are not exhaustive logs of every status-page event. Providers do not disclose customer-impact figures, so cost figures are aggregate customer-loss estimates from analyst reports and revenue-at-risk modeling (the Oct 2025 figure is CyberCube's preliminary insured-loss range). Updated June 2026.
Combined Outage Timeline (Most Costly, Recent)
| Date | Provider | What Happened | Est. Cost |
|---|---|---|---|
| Jul 2026 | AWS | CloudFront VPC Origins control-plane failure; Frankfurt AZ (euc1-az2) capacity limit served global 5xx ~3.5h; Canvas, Blackboard, Hugging Face, UK National Lottery hit | $15M+ est. |
| May 2026 | AWS | us-east-1 (use1-az4) data-center cooling/thermal event; EC2/EBS, ELB, EKS, Redshift, MSK offline ~28h; Coinbase down ~7h | $25M+ est. |
| Feb 2026 | Azure | Remediation workflow disabled anonymous read on storage hosting VM extension packages; VM/VMSS/AKS provisioning failed multi-region ~12h, then Managed Identities token failures in East US & West US | Not quantified |
| Nov 2025 | Cloudflare | Config-propagation failure degraded a large share of the web (~2.4B users routed through Cloudflare) | $250M+ est. |
| Oct 2025 | AWS | DynamoDB DNS race condition cascaded to EC2/Lambda/STS; ~70K orgs | $38-581M insured (CyberCube) |
| Oct 2025 | Azure | Front Door data-plane config change failed globally (~8.5h); cascaded to M365, Outlook, Copilot, Azure Portal, Xbox; Alaska Airlines, Costco, Starbucks hit | Not yet quantified |
| Jun 2025 | GCP | Invalid quota policy crashed Service Control; IAM auth failed across dozens of products; cascaded to Cloudflare, Spotify, Discord, OpenAI | $50M+ est. |
| Jul 2024 | CrowdStrike / Azure | Falcon sensor update crashed Windows hosts globally, incl. Azure VMs; airlines, banks, hospitals hit | $5.4B (Fortune 500, Parametrix) |
| Jan 2023 | Azure | Global WAN/BGP router config change broke connectivity across Azure and Microsoft 365 (Teams, Outlook, SharePoint) worldwide (~5h) | Not quantified |
| Dec 2021 | AWS | us-east-1 EC2/ECS/Lambda/SNS outage (~7h), major global disruption | $150M+ est. |
| Feb 2017 | AWS | S3 us-east-1 outage (~4h) disrupted a large portion of the internet | $150M+ est. |
Per-provider chronologies: AWS, Azure, GCP. CrowdStrike was a software-update incident, not a cloud-provider failure, but it crashed Windows hosts including Azure VMs - see the CrowdStrike case study.
SLA Credits: What Each Cloud Actually Pays
| Provider (service) | Lower-tier credit | Maximum credit | Claim window |
|---|---|---|---|
| AWS (EC2) | 10% (<99.99%) | 30% (<99%) | 30 days |
| Azure (most services) | 25% (99%-99.99%) | 100% (<99%) | Auto for some since 2024 |
| GCP (Compute Engine) | 10% (99%-99.95%) | 50% (<95%) | 30 days |
All credits are a percentage of the monthly fee for the affected service, applied to future invoices - never your revenue loss. Full SLA credit vs actual loss analysis, or calculate your own exposure.