How to Move On-Premise Infrastructure to the Cloud: A Step-by-Step Migration Guide

Global cloud spending is forecast to surpass $1 trillion by the end of 2026, according to Forrester Research. Meanwhile, McKinsey reports that organisations modernising legacy systems through cloud adoption can reduce IT costs by nearly 40% while also accelerating software release cycles. But those results only really show up when the migration is mapped, planned, and carried out properly. If you rush it, or you treat scope like it’s optional, moving from on-premise to cloud can bring downtime, data integrity problems, and security gaps, that end up costing way more than the “savings” you expected.

This guide goes through it all, the right strategy, a step by step process, the key cost items, and then a post migration checklist, so you can move your infrastructure with confidence.

What Is On-Premise to Cloud Migration?

On-premise to cloud migration is basically the process where you shift your applications, data, workloads, and IT infrastructure from physical servers and local data centers to cloud-based environments, could be public like AWS, Azure, Google Cloud , or it might be private, or even hybrid too. So in other words, you are trading away the capital expense of hardware, cooling systems, and those ongoing maintenance contracts, for more operational flexibility and elastic resources, with that pay as you go type of model.

Why Move from On-Premise Systems?

Most organisations end up at some kind of tipping point where the on-premise infrastructure just stops really making sense. Usually, it comes up when it’s time to upgrade hardware, businesses have to decide whether to invest in new servers or finally move to the cloud. Also when there’s a sudden scaling need that the physical stack can’t meet fast enough. Then there’s the security or compliance angle, where cloud-native tooling handles certain requirements more cleanly, plus sometimes there’s just a talent shortage. When managing legacy infrastructure becomes harder to staff, that alone can nudge you over the edge.

But beyond those reactive triggers, the proactive story is actually pretty compelling. If you want to understand what successful cloud adoption looks like, it helps to see that cloud migration isn’t merely a “tech upgrade”. It’s a shift in the way a business operates, where infrastructure becomes a business enabler instead of a constant maintenance burden. You get faster deployment cycles, built-in disaster recovery, global reach, and easier access to managed AI and analytics services. Those are advantages that, on-premise setups can’t match in an economically sensible way.

Planning Your Migration Strategy: The 6Rs Framework

And before moving even a single workload, you need a strategy. Not every application should be migrated the same, no. The 6Rs framework helps you keep it structured, so you can decide how each one should be treated and where it fits.

What Are the Different Cloud Migration Strategies?

Strategy	What It Means	Best For
Rehost	Lift-and-shift, move the application as-is to cloud infrastructure with no changes	Speed priority; legacy apps not worth re-engineering; quick wins
Replatform	Lift, tinker, and shift, minor adjustments (e.g. swapping database engine) to improve cloud efficiency without full rearchitecting	Apps that benefit from managed cloud services with minimal change risk
Refactor	Re-architect the application to be cloud-native, often using microservices, containers, or serverless	High-value apps where performance, scalability, or cost reduction justifies investment
Repurchase	Drop the existing solution and move to a SaaS alternative (e.g. replace on-premise CRM with Salesforce)	Legacy software with a mature cloud equivalent available
Retain	Keep the application on-premise, migration does not make sense yet due to compliance, latency, or cost	Highly regulated data, applications near end-of-life, or recent major investment
Retire	Decommission the application, it no longer provides business value	Redundant systems, duplicate functionality, abandoned tools

Before moving to the cloud, businesses should first review all their applications, how they work, their dependencies, current performance, and overall business importance. This helps them choose the right cloud migration strategy. Skipping this step and simply moving everything to the cloud is one of the biggest reasons why cloud migrations end up costing more and delivering fewer benefits than expected.

On-Premise to Cloud Migration Steps: Step-by-Step Process

Once your strategy is set, the migration itself follows a structured sequence. But if you rush any stage, it compounds risk in the ones that come after it. And nobody wants that later.

• Discovery and assessment – inventory all servers, applications, databases, and all their dependencies. Tools like Azure Migrate, AWS Application Discovery Service, or Google Cloud’s Rapid Assessment programme can automate much of this. Also document current performance baselines so you have something to validate against, after the migration, not before.
• Define objectives and success metrics – establish measurable goals, before you start. Cost targets, performance thresholds, uptime requirements, and compliance standards should be defined and agreed with business and technical stakeholders, at this stage.
• Choose your cloud provider and architecture – pick a provider that lines up with your technical requirements, existing licences, and geographic data residency needs. Then design your target architecture, network topology, identity and access management security controls, and storage structure, before migrating anything at all.
• Build and test the landing zone – set up your cloud environment: virtual networks security groups IAM policies, logging, and monitoring infrastructure. Test this environment thoroughly first, before it receives production workloads, even if it feels tempting to move faster. Working with advanced cloud data migration specialists at this stage significantly reduces architecture errors that are expensive to fix later.
• Migrate in waves, not all at once - start with low-risk, non-critical workloads to build confidence and validate your tooling and processes. Progressively migrate more critical systems. Maintain a parallel-run period for each wave where on-premise systems remain operational until cloud systems are fully validated
• Test thoroughly at each wave - validate functionality, performance, integration points, and security posture for each migrated workload before decommissioning the on-premise equivalent
• Cut over and decommission - once cloud systems are validated and stable, formally cut over, update DNS and routing, notify stakeholders, and begin decommissioning on-premise infrastructure in a controlled sequence.

For Azure cloud migration, Microsoft's Azure Migrate hub provides an integrated toolset for discovery, assessment, and migration execution, significantly reducing the manual effort of the early stages for organisations standardising on the Azure ecosystem.

Cloud Migration Cost Management and Optimisation

One of the most common post-migration surprises is a cloud bill that is higher than anticipated. This almost always traces back to one of three issues: over-provisioning (migrating resources at their peak on-premise size rather than right-sizing for actual usage), unused resources left running after testing, or a failure to select the right pricing model (on-demand vs reserved vs spot instances).

Cost management starts before migration. Adjust every workload based on how it is actually being used, instead of simply copying the specifications of the old server. Implement tagging policies from day one so every resource has an owner, a cost centre, and the right environment. Set up budget alerts immediately. And factor in savings opportunities: reserved instances typically offer 30–72% savings over on-demand pricing for workloads with predictable usage patterns.

Working with data migration experts who have experience with cloud cost architecture, not just the technical migration, prevents the over-provisioning patterns that inflate cloud spend in the first 6–12 months post-migration.Scalable cloud solutions at this stage also help ensure your infrastructure can grow efficiently without unnecessary resource costs. 

On-Premise to Cloud Migration Checklist and Post-Migration Optimisation

Pre-Migration Checklist

• Full application and dependency inventory completed
• 6Rs strategy applied to each workload
• Target cloud architecture designed and reviewed
• Landing zone built and security baseline established
• Performance baselines documented for all critical workloads
• Rollback plan defined for each migration wave
• Data backup verified before any workload moves
• Team trained on cloud platform tooling and monitoring

Post-Migration Checklist

• All workloads validated against pre-migration performance baselines
• Security posture reviewed, IAM policies, network controls, encryption at rest and in transit
• Monitoring and alerting configured for all production workloads
• Cost dashboards active with budget alerts set
• On-premise systems decommissioned in a controlled sequence
• Documentation updated to reflect new cloud architecture
• Disaster recovery tested in the cloud environment

Post-Migration Optimisation

Migration is not the finish line, it is the starting point for cloud-native optimisation. In the weeks and months following cutover, review resource utilisation across all workloads and right-size anything that is consistently over or under-provisioned. Identify workloads that could benefit from autoscaling. Evaluate whether any Rehost migrations now justify Refactoring to take advantage of cloud-native services. Implement a FinOps practice, regular cost review meetings with cross-functional ownership, to keep cloud spend aligned with business value.

Why Choose Dotsquares for Your On-Premise to Cloud Migration?

Cloud migration is technical, but its success mostly depends on making the right strategic decisions. Picking the wrong architecture, downplaying how entangled dependencies get, or moving without a crisp cost governance model are slip ups that seem “fine” at first, until they start to compound into a programme that ends up costing twice as much as expected and giving only about half of what was promised.

Dotsquares brings end-to-end capability across the full migration journey, from discovery and custom cloud architecture advising through actual migration execution, security hardening, and then post-migration optimisation. Our teams have delivered cloud migrations across AWS, Azure, and Google Cloud for clients spanning fast-growing SMEs to large enterprise organisations, often with complex multi-system landscapes.

• Proven methodology - a structured delivery framework built from hundreds of successful cloud migration engagements
• Security-first approach - cloud security services integrated from architecture design, not added after cutover
• Cost governance - right-sizing and FinOps practices built-in into every engagement to prevent those cloud bill surprises
• Hire data migration experts, dedicated cloud migration engineers, instead of generalist consultants who get reassigned to a project and then vanish
• Post migration support - ongoing optimisation and managed cloud services available after the initial migration programme, not only for the short stretch when it goes live