Loads of businesses find that migrating from AWS to Azure opens up possibilities they didn’t have before.
Some achieve cost savings of 30% or more (particularly those with existing Microsoft licences). Others enjoy some brilliant operational improvements and ecosystem integration.
Below, we’ll look at why businesses are making this move, how to approach it successfully, and what you need to know for a smooth changeover.
If your organisation runs on Microsoft 365, Teams, and SharePoint, AWS integration always feels like a workaround. Azure changes this completely: Teams performs better, SharePoint syncs smoothly, and single sign-on through Entra ID actually works as intended. The integration extends to Power BI, Dynamics 365, and Windows Virtual Desktop. These aren’t minor improvements; they transform daily productivity across your organisation.
Azure isn’t automatically cheaper than AWS. The 30% savings some organisations report typically requires existing Microsoft licences and smart architectural choices. Where Azure delivers value: Azure Hybrid Benefit converts existing Windows Server and SQL Server licences into cloud savings (up to 40% for Windows Server). And Enterprise Agreements make sense if you’re already committed to Microsoft 365. The real financial benefit often comes from eliminating the ‘complexity tax’ of running across multiple platforms.
Both AWS and Azure operate UK data centres and meet GDPR requirements. Azure differentiates through integration with the Microsoft compliance framework you’re likely already using. Microsoft Purview provides unified governance across Azure, Microsoft 365, and on-premises data – you’re not learning new compliance tools or maintaining separate policies.
For organisations already invested in Microsoft’s compliance ecosystem, this familiarity reduces administrative overhead in a big way.
Microsoft’s AI investment over the last couple of years shows in Azure’s integrated AI services. While AWS offers excellent AI capabilities through SageMaker and Bedrock, Azure AI integrates naturally with Microsoft Graph data, Teams, and your existing security frameworks.
There’s also Microsoft’s deep ties with OpenAI, of course. For companies deep in the Microsoft stack, this integration often tips the scales.
Before you start planning your Azure future, you need to understand your AWS present. This means more than just listing your EC2 instances and S3 buckets. You need to map out the entire ecosystem: the dependencies, the data flows, the identity management, and the network topology.
Start by documenting:
Pay special attention to AWS-specific services that don’t have direct Azure equivalents. That clever Lambda function using AWS-specific APIs will need rethinking. The DynamoDB table with complex queries might need a different approach in Azure.
Getting a grip on the service equivalents helps you plan, but don’t fall into the trap of one-to-one mapping. Here’s how the major services in each cloud platform line up:
Compute:
⠀Storage:
⠀Database:
⠀Networking:
Remember, these aren’t perfect matches. Azure services often have different features, pricing models, and performance characteristics. Sometimes the Azure equivalent is actually several services working together. Conversely, one Azure service might replace multiple AWS services.
You’ve got three main strategies for moving from AWS to Azure:
Rehost (Lift and Shift): Moving your workloads ‘as-is’ to Azure. Quick but misses optimisation opportunities. Good for stable, well-understood applications that just need to move quickly.
Refactor: Modifying applications to take advantage of Azure-native features. Takes longer but delivers better performance and cost efficiency. Perfect for applications that’ll benefit from Azure PaaS services.
Rearchitect: Completely redesigning for cloud-native Azure services. Maximum effort but also maximum benefit. Ideal for legacy applications that need modernisation anyway or systems where the current architecture is holding you back.
Most successful migrations use a combination. Maybe you lift-and-shift production systems for speed, then refactor them once they’re running on Azure. Or you rearchitect customer-facing applications while rehosting internal tools.
A solid AWS to Azure migration checklist keeps everything on track. Here’s what you need:
Pre-migration phase:
⠀Migration phase:
⠀Post-migration phase:
Success starts with solid foundations. Your Azure environment needs to be ready before you move a single workload. This means setting up your Azure tenant properly, not just creating a subscription and diving in.
Start with governance. Establish your management groups, subscriptions, and resource groups structure. This might seem like bureaucracy, but getting it right now saves massive headaches later. Create naming conventions that make sense for your organisation. Set up cost management boundaries and define your tagging strategy.
Security can’t be an afterthought. Configure Entra ID (formerly Azure AD) with proper conditional access policies. Set up privileged identity management for admin access. Enable Azure Security Centre (now Microsoft Defender for Cloud) from day one. These aren’t things you can easily retrofit once workloads are running.
Your landing zone is essentially your Azure foundation: the environment where all your migrated workloads will live. Microsoft provides landing zone templates, but don’t just deploy them blindly. Customise them for your needs.
Network architecture needs careful thought. Hub-and-spoke, full mesh, or virtual WAN? The choice affects everything from performance to costs. Plan for hybrid connectivity if you’re keeping anything on-prem or maintaining multi-cloud setups. ExpressRoute might seem expensive, but it could be essential for large-scale data migration and ongoing operations.
If you’re comfortable with Infrastructure as Code (IaC), consider using Deployment Stack to standardise deployments. Create templates for common scenarios: web applications, databases, backend services. This brings consistency and compliance across all your migrated workloads.
Moving from AWS IAM to Azure Entra ID isn’t just a terminology change. The whole philosophy is different. AWS thinks in terms of roles and policies attached to resources. Azure thinks about identities and their permissions across the entire platform.
So, start by mapping your AWS IAM roles to Azure RBAC roles. You’ll probably find Azure’s built-in roles cover most scenarios, but don’t hesitate to create custom roles for specific needs. Remember that Azure has management groups above subscriptions, giving you another layer of access control that AWS lacks.
AWS VPCs and Azure Virtual Networks look similar on the surface but behave differently underneath. Azure VNets are regional constructs that can span availability zones automatically. No more managing multiple VPCs across availability zones.
Security groups work differently too. Azure Network Security Groups are separate resources that you attach to subnets or network interfaces. They’re more flexible than AWS security groups but require different thinking about traffic flow and rule management.
Don’t forget about DNS. Route 53 doesn’t exist in Azure, but Azure DNS and Private DNS zones provide similar functionality. If you’re using Route 53 for complex routing policies, you might need Azure Traffic Manager or Front Door as well.
Azure’s security model builds on the Microsoft security stack you might already know. Microsoft Defender for Cloud provides unified security management across Azure, on-premises, and even other clouds (yes, including AWS).
You’ll also want to enable Azure Policy from the start. Unlike AWS Config, Azure Policy can actually enforce compliance, not just report on it. Create policies for your organisation’s requirements: approved VM sizes, required tags, allowed regions, encryption standards.
Set up Azure Monitor and Log Analytics workspaces. You’ll want everything logging to a central location from day one. The logs are invaluable for troubleshooting migration issues and establishing baselines for normal operation.
VM migration seems straightforward: it’s just moving virtual machines, right? The reality is a bit more nuanced, though. Azure VMs have different size families, performance characteristics, and pricing models than EC2 instances.
Start by right-sizing. That m5.xlarge instance might map to a D4s_v5 in Azure, but is that really what you need? Azure’s B-series burstable VMs could save significant money for variable workloads. Premium SSD v2 storage might eliminate the need for provisioned IOPS.
Azure Migrate can automate much of the heavy lifting. It’ll discover your EC2 instances, assess compatibility, and even handle the replication. But don’t just click and migrate. Review the recommendations, understand the network requirements, and plan for cutover windows.
Consider using Azure’s managed disks from the start. They’re simpler than managing your own storage accounts and provide better reliability. Availability sets or availability zones? Depends on your application architecture and SLA requirements.
S3 and Azure Blob Storage serve similar purposes but have different approaches to organisation and access. S3’s flat namespace with prefixes becomes Azure’s container-based hierarchy. S3’s complex permission system becomes Azure’s combination of RBAC and SAS tokens.
Data migration tools are abundant. AzCopy handles large-scale transfers efficiently. Azure Data Factory provides orchestration for complex migration patterns. For massive datasets, Azure Data Box might be the answer: sometimes shipping physical drives beats network transfer.
Watch out for:
Database migration requires the most careful planning. Downtime tolerance, data consistency requirements, and application dependencies all factor into your strategy. Azure Database Migration Service (DMS) supports online migrations for many database engines. You get minimal downtime, continuous sync during migration, and automatic cutover. But it’s not magic: schema compatibility, data types, and database features need careful assessment.
For SQL Server workloads, Azure SQL Database might not be the only option. Azure SQL Managed Instance provides near 100% SQL Server compatibility. Azure VMs with SQL Server give you complete control. The choice affects everything from costs to maintenance burden.
Think about whether this migration is also a modernisation opportunity. That MySQL database might work better as Azure Database for MySQL, or it might be time to move to Azure Cosmos DB for global distribution and multi-model support.
Lambda functions don’t just lift and shift to Azure Functions. The execution models, triggers, and runtime environments differ enough that you’ll need code changes.
Key differences to handle:
Azure Functions integrate beautifully with other Azure services. Service Bus triggers, Cosmos DB bindings, and Event Grid integration often eliminate complex Lambda orchestration patterns.
Consider whether Azure Container Apps might be a better fit for some Lambda workloads. They provide more control over the runtime environment and better support for long-running processes.
Cloud migration isn’t just about moving workloads – it’s about avoiding the pitfalls that can turn a strategic move into an expensive mistake. Here are the main AWS to Azure migration challenges to watch for:
Azure Migrate is a hub of migration services. Its discovery and assessment tools understand your AWS environment, map dependencies, and estimate Azure costs. The migration tools handle the actual workload movement.
The Server Migration feature supports agentless migration for many workloads. Install the replication appliance, configure replication, and test migrations without touching production. When you’re ready, cut over with minimal downtime.
Database Migration Service handles your data tier. Online migrations keep databases available during replication. Offline migrations are simpler but require downtime. The Schema Migration Tool helps convert database objects for Azure SQL targets.
Beyond Azure Migrate, several third-party tools can help with specific migration scenarios. Tools like Turbonomic provide workload optimisation recommendations, while your existing backup solutions (Veeam, Commvault, Rubrik etc.) might offer cross-cloud recovery options that simplify migration. Choose based on your specific needs and complexity.
Before committing to migration, use assessment tools to understand costs and compatibility:
For a useful overview of migration services, check out our detailed guide to Azure migration tools.
The first morning after cutover tells you whether your migration succeeded or just finished. Users logging in should find familiar applications running faster, especially Microsoft-integrated workloads. Your administrators should see simplified management, not new complexity.
Common improvements include genuine single sign-on, faster Microsoft 365 performance, and clearer cost tracking without third-party tools.
Migration gets you to Azure. Optimisation makes Azure work for you. Start with the low-hanging fruit:
⠀Then tackle deeper optimisation:
Azure Cost Management provides the visibility you need. Set budgets, create alerts, and track spending by project, department, or any dimension that matters to your business. For more strategies on controlling costs, see our guide to Azure Cost Optimisation.
Azure’s integrated management tools reduce operational overhead. Azure Monitor provides unified monitoring and alerting. Azure Automation handles repetitive tasks like patching and scaling. Azure Policy enforces compliance standards automatically. Microsoft Defender for Cloud secures your environment with Azure-native understanding that third-party tools can’t match.
At Synextra, we’ve guided many UK businesses through successful Azure migrations.
Whether you need hands-on migration support or architecture guidance, we bring the expertise that makes complex migrations manageable. And our migration assessment helps you understand what moving to Azure means for your specific situation.
Ready to explore your options? Get in touch to start your migration journey with confidence.
