AWS to Azure Migration: Service Mapping & Process
Moving from AWS to Azure is very doable with a clear service map and a staged plan. Here's why teams move, how the services line up, and how to migrate without downtime.
- Teams move from AWS to Azure mainly for Microsoft and .NET integration, enterprise agreements and consolidation, not because one cloud is technically 'better'.
- Most AWS services have a clear Azure equivalent, so migration is largely about mapping services, moving data and re-testing rather than rewriting everything.
- Effort scales with your architecture, data volume and managed-service use; clean, modern apps move easily while tightly-coupled ones need work.
- A staged migration with data sync and a rehearsed cutover (or parallel-run for critical systems) avoids downtime and keeps rollback on the table.
AWS to Azure migration is very achievable because the two clouds map closely: for most workloads it is service translation, data movement and re-testing rather than a rewrite. Teams usually move for a business reason - tighter Microsoft and .NET integration, an enterprise agreement, or consolidation onto one cloud - not because Azure is technically superior. Almost every core AWS service has a direct Azure equivalent (EC2 to Virtual Machines, S3 to Blob Storage, RDS to Azure SQL, Lambda to Functions), so the work is mostly mapping, re-platforming where it pays off, and rehearsing the cutover. This guide covers why teams move, how the services line up, the migration approaches and process, what drives cost and timeline, and how to cut over without downtime.
Why Teams Move From AWS to Azure
Most AWS to Azure migrations are driven by fit, not by any shortcoming in AWS. The strongest reasons are almost always about integration, commercial terms and reducing operational sprawl:
- Microsoft and .NET integration - a tighter fit with Microsoft 365, Active Directory / Microsoft Entra ID and .NET workloads.
- Enterprise agreements - bundling and discounts through an existing Microsoft relationship.
- Consolidation - standardising on one cloud to cut complexity, tooling and management overhead.
- Specific Azure services, region coverage or compliance and data-residency needs.
Migrate for a real business reason - integration, cost or consolidation - not because Azure is 'better'. Both clouds are excellent; the value is in the fit.
How AWS Services Map to Azure
Most AWS services have a clear Azure equivalent, which is what makes migration a translation exercise rather than a rebuild. The table below covers the mappings you will meet most often; identity is usually the one that needs the most re-thinking, because IAM policies do not port one-to-one to Microsoft Entra ID and Azure RBAC.
| AWS Service | Azure Equivalent | Notes |
|---|---|---|
| EC2 | Azure Virtual Machines | Direct rehost target; re-check VM sizing |
| S3 | Azure Blob Storage | Similar model; access controls differ |
| RDS | Azure SQL Database / Azure Database for PostgreSQL | Managed DB; watch engine and version parity |
| Lambda | Azure Functions | Serverless; triggers and runtimes need mapping |
| EKS | Azure Kubernetes Service (AKS) | Containers move cleanly if manifests are portable |
| IAM | Microsoft Entra ID / Azure RBAC | Redesign, do not port; identity model differs |
| CloudWatch | Azure Monitor / Log Analytics | Rebuild dashboards and alerts |
Identity is the mapping to plan first. IAM does not translate directly to Entra ID and Azure RBAC, so treat it as a redesign, not a copy.
Migration Approaches: Rehost, Re-Platform or Modernize
There is no single right way to migrate; you choose an approach per workload. Rehosting (lift and shift) moves a workload as-is, re-platforming swaps in Azure managed services, and modernising re-architects for the cloud. The decision matrix below shows when each fits.
| Approach | Best When | Effort | Cloud Benefit Captured |
|---|---|---|---|
| Rehost (lift and shift) | You need to exit AWS quickly or the app is stable | Low | Lower |
| Re-platform | You want managed services (Azure SQL, AKS) with minimal code change | Medium | Moderate |
| Modernize / re-architect | The workload is high-value and worth optimising | High | Higher |
A common, sensible pattern is to rehost first to move off AWS quickly, then modernise the highest-value workloads over time rather than boiling the ocean up front.
The AWS to Azure Migration Process
A repeatable migration follows the same staged path regardless of workload. Test everything before the real cutover, and never move production data without a rehearsed rollback.
- Assess - inventory AWS resources, dependencies and data, and map them to Azure equivalents.
- Plan - choose rehost, re-platform or modernise per workload, and design the Azure landing zone.
- Set up Azure - build networking, identity (Entra ID), security and CI/CD pipelines.
- Migrate in test - move workloads and data to a test environment first and validate thoroughly.
- Sync data - replicate and keep data current right up to the cutover point.
- Cut over - switch in a planned window with a rollback option ready.
- Optimise - right-size resources in Azure and tune cost and performance after go-live.
What Drives Cost and Timeline
Cost and timeline scale with your architecture, data volume and how many managed services need translating, not with a fixed price list. Clean, modern applications move easily; tightly-coupled or legacy systems need work before they will run well on Azure. These are the qualitative factors that move the effort up or down:
Planning an AWS to Azure Migration?
We'll map your AWS estate to Azure, recommend the right approach per workload, and deliver the migration with a rehearsed, low-risk cutover.
How to Migrate Without Downtime
You can migrate from AWS to Azure without downtime by staging the move and keeping rollback available at every step. The principle is simple: never cut over cold. Prove the workload in a test environment, keep data in sync, and switch only when Azure is validated.
- Migrate to a test environment on Azure first and validate the workload end to end before touching production.
- Keep data replicated and in sync right up to the cutover so no records are lost in the switch.
- Cut over in a rehearsed, planned window with a tested rollback path.
- For critical systems, run both clouds in parallel and shift traffic gradually instead of a single hard switch.
- Right-size in Azure after go-live rather than copying AWS sizing blindly, or you will overpay.
Common Mistakes to Avoid
Most migration pain comes from a handful of avoidable mistakes rather than from anything inherent to Azure. The ones we see teams get wrong most often:
- Copying AWS instance sizing straight into Azure and overpaying, instead of right-sizing to Azure's SKUs.
- Treating IAM as a direct port to Entra ID rather than redesigning the identity and access model.
- Skipping the test-environment stage and cutting over production cold, with no rehearsed rollback.
- Trying to modernise everything at once instead of rehosting first and modernising the high-value workloads later.
- Underestimating data volume, so the sync and cutover window blows out on the day.
- Forgetting to rebuild monitoring and alerting (CloudWatch to Azure Monitor) before go-live, so you fly blind after cutover.
How Acqurio Tech Approaches AWS to Azure Migration
We migrate workloads between clouds and run them well afterwards, mapping your AWS estate to Azure and choosing the right approach per workload rather than forcing one strategy on everything. Our teams cover the migration and the operate phase that follows:
- Cloud & DevOps - migration, landing zones, CI/CD and ongoing cost optimisation.
- Azure and AWS - deep, hands-on expertise in both clouds.
- Hire DevOps engineers - pre-vetted cloud migration talent to extend your team.
Conclusion
AWS to Azure migration is very achievable because the two clouds map closely - it is mostly service translation, data movement and re-testing, not a rewrite. Move for a real reason like Microsoft integration or consolidation, map services carefully (identity first), pick the right approach per workload, and stage the cutover with data sync and a rollback plan to avoid downtime. Right-size in Azure afterwards, and the migration becomes a controlled, low-risk exercise rather than a leap of faith. If you want a service map and a phased plan for your estate, get in touch.
Frequently asked questions
How do I plan an AWS to Azure migration?
Start by assessing and inventorying your AWS resources, dependencies and data, then map each service to its Azure equivalent and choose an approach per workload (rehost, re-platform or modernise). Build the Azure landing zone, migrate to a test environment first, keep data in sync, and cut over in a rehearsed window with rollback ready. A staged plan like this keeps an AWS to Azure migration controlled rather than risky.
Why migrate from AWS to Azure?
Usually for tighter Microsoft and .NET integration (with Microsoft 365, Entra ID and .NET workloads), enterprise agreements and discounts through an existing Microsoft relationship, consolidation onto one cloud, or specific Azure services and compliance needs - not because Azure is technically better than AWS.
How do AWS services map to Azure?
Most have clear equivalents: EC2 to Azure VMs, S3 to Blob Storage, RDS to Azure SQL or Azure Database for PostgreSQL, Lambda to Azure Functions, EKS to AKS, and IAM to Microsoft Entra ID and Azure RBAC. This close mapping makes migration largely a translation exercise, though identity usually needs redesigning rather than a direct port.
Can I migrate from AWS to Azure without downtime?
Yes, with a staged approach: migrate to a test environment first, keep data in sync, and cut over in a rehearsed window with a rollback plan. For critical systems you can run both clouds in parallel and shift traffic gradually to eliminate downtime.
What does an AWS to Azure migration cost?
There is no flat figure - it depends on your architecture, data volume and managed-service use. Rehosting is cheaper than re-platforming or modernising. An assessment that maps your AWS estate to Azure produces a realistic, phased estimate, and right-sizing in Azure controls ongoing run cost.
Should I rehost or modernise during the migration?
It depends per workload. Rehosting (lift and shift) is fastest and lowest-risk but captures less cloud benefit; re-platforming to Azure managed services or modernising delivers more but takes more effort. Many teams rehost first to move quickly, then modernise the highest-value workloads over time.
Is AWS to Azure migration difficult?
It is very achievable because the clouds map closely. The effort depends on your architecture (clean apps move easily, tightly-coupled ones need work), data volume and how many managed services need translating. A staged plan with testing and data sync keeps it controlled.