AWS vs Azure for SaaS Companies

Both clouds will run your SaaS. The decision is rarely technical capability and almost always some combination of team skills, commercial terms and customer requirements. Here is where they genuinely differ in day-to-day engineering.

Managed Kubernetes

EKS gives you more control and more assembly: node management through Karpenter or managed node groups, add-ons chosen explicitly, and IRSA for workload identity. AKS is more opinionated and faster to a working cluster, with tighter Entra ID integration. Teams with strong Kubernetes experience often prefer EKS; teams who want fewer decisions often prefer AKS.

Databases

Aurora on AWS is the strongest managed Postgres story for scaling read traffic and separating storage from compute. Azure Database for PostgreSQL Flexible Server is solid and simpler to reason about. If your workload is Postgres-heavy with unpredictable read scaling, that is a real point for AWS.

Identity and enterprise sales

If your customers are enterprises already standardised on Microsoft, Azure's identity integration and marketplace presence can shorten procurement. This is a commercial advantage that outweighs most technical differences when it applies.

Cost behaviour

• AWS: data transfer and NAT Gateway processing are common surprise line items; savings plans are flexible across instance families.
• Azure: reservations are more rigid but Hybrid Benefit is significant if you already hold Windows or SQL Server licensing.
• Both: the largest costs are architectural, and the difference between the two clouds is usually smaller than the difference a good architecture makes on either.

Ecosystem and hiring

AWS has a deeper third-party tooling ecosystem and a larger pool of engineers with production experience. Azure's tooling has closed much of the gap, but if you are hiring platform engineers in a competitive market, AWS experience is more common.

The criteria that should decide it

• What your current engineers can operate on-call without a training programme.
• What your customers require contractually — residency, certifications, marketplace.
• What commercial terms you can actually negotiate at your spend level.
• Which managed services remove the most operational work for your specific workload.

On multi-cloud

Running both by default doubles the operational surface and forfeits the depth of each provider's managed services. Multi-cloud is justified by a concrete requirement — a customer contract, a regulatory rule, a specific service that exists in only one place — not by a general preference for optionality.