On-Premises to Cloud Migration: Step-by-Step Process and Checklist

On-premises to cloud migration moves your company’s servers, data, and applications off local hardware and onto a cloud provider’s infrastructure, such as AWS, Azure, or Google Cloud. The process follows a sequenced plan: assess your environment, classify each workload, choose a migration strategy, execute in phases, and validate the results. This guide gives you every step and a practical checklist to use from day one.

Key Takeaways

Cloud migration starts with a full workload inventory. Skipping this step causes most migration failures.
The 7 Rs framework (Rehost, Replatform, Refactor, Repurchase, Retain, Retire, Relocate) guides workload decisions.
Phased migration reduces downtime risk. Start with low-risk workloads before moving production systems.
A tested rollback plan is required before any production cutover.
Post-migration cost monitoring is an ongoing process, not a one-time setup task.

What Is On-Premises to Cloud Migration and What Does It Include?

On-premises to cloud migration is the process of moving your organization’s data, applications, and computing workloads from physical servers you manage internally to cloud-based infrastructure managed by a third-party provider. You stop paying to maintain local hardware and start paying for the computing power and storage you actually use.

Cloud infrastructure shifts that responsibility to the provider. AWS, Microsoft Azure, and Google Cloud own and operate the physical hardware. You access their resources over the internet and pay based on consumption, a model known as pay-as-you-go pricing.

Migration typically includes three destination types: public cloud (infrastructure shared across many customers, such as AWS or Azure), hybrid cloud (a combination of on-premises systems and cloud resources running together), and multi-cloud (using services from more than one cloud provider simultaneously). Most small-to-mid-size businesses start with public cloud and move to hybrid configurations as their needs become clearer.

The business case is straightforward. You eliminate hardware refresh cycles, reduce data center costs, and give your team the ability to scale compute resources up or down based on actual demand.

What Are the Different Types of Cloud Migration Strategies Available?

The 7 Rs framework gives you a decision tool for each workload. Every application or database in your environment should map to one of these seven strategies before migration begins. Choosing the wrong approach for a workload is one of the most expensive mistakes an IT team can make.

Rehost (Lift-and-Shift): Move the application to the cloud with no changes to its code or architecture. Best for workloads that need to move quickly and don’t require cloud-native features.
Replatform: Make minor adjustments to take advantage of cloud capabilities without rewriting the application. Example: moving a database to a managed database service like Amazon RDS.
Refactor: Redesign the application to be cloud-native. This takes the most time but delivers the most performance and cost benefits long-term.
Repurchase: Replace the on-premises application with a SaaS (Software as a Service) alternative. SaaS means software delivered entirely over the internet, like replacing your local email server with Microsoft 365.
Retain: Keep the workload on-premises because it’s not suitable for cloud migration yet, or because regulatory requirements restrict its location.
Retire: Decommission applications that are no longer needed. A workload audit almost always reveals redundant systems that cost money to maintain and add nothing.
Relocate: Move infrastructure to the cloud provider’s environment without any architectural changes. Used when migrating virtualized environments at scale.

Most SMB migrations rely heavily on Rehost and Repurchase. Rehost gets workloads into the cloud quickly. Repurchase eliminates maintenance overhead by replacing custom or legacy software with a managed SaaS product. Refactor is worth the investment for business-critical applications where performance and cost efficiency matter over years, not months.

What Are the Step-by-Step Stages of an On-Premise to Cloud Migration?

A successful on-premise to cloud migration follows seven sequential steps. Skipping steps, particularly the assessment and security planning phases, leads to data integrity issues, cost overruns, and extended downtime. Follow this order and treat each step as a gate before proceeding to the next.

Assess your current environment. Audit every server, application, database, and network dependency in your on-premises environment. Document data volumes, software versions, licensing terms, and how systems connect to each other. This dependency mapping prevents surprises during cutover. An application that silently relies on a local file share will break if you migrate it before its dependencies.
Define migration goals. Set measurable targets before you commit to a provider or timeline. Goals might include reducing infrastructure costs, achieving 99.9% uptime (a standard service level agreement, or SLA, that cloud providers offer), or enabling remote access for a distributed team.
Choose your cloud provider and deployment model. Select between public cloud, hybrid cloud, or multi-cloud based on your workload requirements, existing software stack, and budget. Provider selection matters. AWS, Azure, and Google Cloud have meaningfully different toolsets, pricing structures, and integration strengths.
Select a migration strategy for each workload using the 7 Rs. Go through your inventory workload by workload. Assign a strategy to each one. This classification determines your timeline, budget, and technical complexity for every item on the list.
Plan for security and compliance. Identify which data sets contain sensitive customer information, financial records, or health data. Map those categories to applicable regulations: GDPR, HIPAA, SOC 2, or others relevant to your industry. Plan encryption in transit and at rest, configure identity and access management (IAM) policies, and schedule a cloud security posture review after migration completes.
Execute the migration in phases. Start with low-risk workloads: development environments, archived data, or internal tools. Validate each phase before proceeding. Move production workloads last, with a tested rollback plan in place. A rollback plan defines exactly how you restore the previous environment if the migration causes production issues.
Test, validate, and optimize after migration. Verify data integrity by comparing checksums between your original and migrated data sets. Monitor application performance against your pre-migration baseline. Right-size your cloud resources, meaning adjust CPU, memory, and storage allocations to match actual usage, to control costs from day one.

What Does an On-Prem to Cloud Migration Checklist Include?

A structured migration checklist keeps each phase on track and prevents the shortcuts that cause failures. The checklist below is divided into three phases: pre-migration, during migration, and post-migration. Skipping items in the pre-migration phase, particularly backup verification and rollback planning, accounts for the majority of migration problems teams encounter.

Pre-Migration Checklist

Complete a full hardware and software inventory with dependency mapping
Classify each workload using the 7 Rs framework
Obtain stakeholder sign-off on migration timeline and downtime windows
Verify backups are current and test restoration before any cutover begins
Review data compliance requirements and confirm your target cloud environment meets them
Confirm network bandwidth between on-premises and cloud is sufficient for data transfer
Document a rollback procedure for every production workload

During-Migration Checklist

Follow the phased cutover schedule. Do not migrate critical systems alongside low-risk workloads
Validate data transfer completeness after each phase using checksums or hash verification
Confirm access control configurations are correct before going live on each workload
Keep the rollback plan accessible and tested throughout the cutover window
Monitor network latency and application response times during migration

Post-Migration Checklist

Run performance benchmarking against your pre-migration baseline
Set up cost monitoring using tools like AWS Cost Explorer or Azure Cost Management
Right-size cloud resources based on actual observed usage, not estimated usage
Decommission on-premises hardware only after a validation period of at least 30 days
Train your team on the new cloud environment, access procedures, and support processes

How Do You Migrate from On-Prem to AWS Cloud Specifically?

AWS provides a set of tools built to cover every stage of the migration process, from initial discovery through post-migration monitoring.

AWS Migration Hub gives you a central dashboard to track the status of all your migrations across AWS tools in one place.

AWS Application Migration Service (MGN) handles server rehosting. It continuously replicates your on-premises servers to AWS and lets you test in the cloud before committing to cutover. This reduces downtime during the final switch to minutes rather than hours.

AWS Database Migration Service (DMS) moves databases to AWS with minimal downtime. It supports migrations between different database engines, so you can move from an on-premises Oracle database to Amazon Aurora without rebuilding your schema from scratch.

AWS DataSync accelerates large data transfers to Amazon S3, Amazon EFS, or Amazon FSx. For organizations moving terabytes of unstructured data, DataSync reduces transfer time compared to manual file copy processes.

On pricing, AWS uses a pay-as-you-go model for compute through services like EC2, with storage billed per gigabyte in S3. Data transfer into AWS is generally free. Transfers out of AWS to the internet incur fees, so plan your data egress costs before migration to avoid surprises. AWS also offers a Migration Acceleration Program (MAP) that provides financial support, training, and migration assistance to qualifying businesses.

How Do You Choose the Right Cloud Provider for Your Migration?

Provider selection comes down to four factors: your existing software stack, your team’s current skills, your compliance requirements, and total cost over three years. A business already running Microsoft 365 and Active Directory will find Azure’s native integration significantly reduces identity and access management complexity. A development team with AWS certifications will move faster on AWS.

Dimension	AWS	Azure	Google Cloud
Primary Migration Tool	AWS Migration Hub + Application Migration Service	Azure Migrate	Google Cloud Migrate
Best Fit For	Broad workload types; largest service catalog	Microsoft-centric environments (M365, Active Directory)	Data analytics and AI/ML workloads
License Cost Savings	AWS License Manager for existing licenses	Azure Hybrid Benefit for Windows Server and SQL Server	Committed use discounts
Free Assessment Tool	AWS Migration Hub (partial)	Azure Migrate (full free assessment)	Google Cloud Migrate assessment tools

Azure Migrate provides a free assessment that maps your on-premises environment and recommends right-sized Azure resources before you commit to any spend. For businesses with existing Windows Server or SQL Server licenses, Azure Hybrid Benefit can reduce cloud compute costs by a meaningful margin.

Google Cloud Migrate is worth evaluating if your migration involves significant data processing or machine learning workloads. Its strength is in analytics and AI, not general-purpose server rehosting.

A 2024 survey of IT decision-makers, according to Google (GCP ITDM Scenarios Research Report), found that 78% of respondents cite cloud migration as a strategic priority for the next 12 months. What separates organizations that complete migrations from those that stall is a concrete workload-level plan. A general desire to move to the cloud is not enough.

Common Migration Risks and How to Manage Them

Four risks cause the majority of on-prem to cloud migration failures: data loss during transfer, unexpected downtime, security misconfigurations, and cost overruns from over-provisioned resources. Each has a concrete mitigation.

Data loss: Run verified, tested backups before any cutover window. “Verified” means you have actually restored from the backup and confirmed data integrity, not just confirmed the backup file exists. Use checksum validation after each data transfer phase to confirm completeness.

Extended downtime: Use phased migration with clear rollback procedures at each stage. AWS Application Migration Service and Azure Site Recovery both support continuous replication that limits production cutover time to minutes. Plan your cutover window during off-peak hours and communicate it to stakeholders in advance.

Security misconfigurations: Cloud environments default to open configurations in some areas. After migration, run a cloud security posture review to check IAM policies, network security groups, storage permissions, and encryption settings. Many providers include basic security assessment tools at no extra cost.

Cost overruns: Over-provisioning is the most common post-migration cost problem. Organizations often size cloud resources to match on-premises specs rather than actual usage. Set up AWS Cost Explorer or Azure Cost Management from day one and review resource utilization within the first 30 days. According to LogicMonitor (cited in a Citrix white paper), 87% of enterprises planned to accelerate cloud migration. Cost control remains the top concern slowing execution across organizations of all sizes.

A tested rollback plan separates teams that can recover quickly from teams that face hours or days of production outage. Write it down, test it in a non-production environment, and confirm the team knows how to execute it before the cutover window opens.

Your Migration Plan Starts with the Inventory

Assess your environment, plan by workload, and execute in phases. Those three sentences describe the migration process in full. The checklist above is the practical tool that keeps each phase honest.

Gartner projects that 90% of businesses will adopt a hybrid cloud approach by 2027, which means most organizations will maintain some on-premises workloads even after a major migration. Understanding which workloads belong in the cloud and which should stay on-premises is as important as knowing how to move them.

Start with your workload inventory. Everything else follows from there. For your next steps, explore our AWS vs. Azure comparison guide to go deeper on provider selection, and review our cloud cost management resources to build your post-migration monitoring plan before you need it.

Frequently Asked Questions

How long does an on-premises to cloud migration take?

Migration timelines vary based on workload complexity and volume. A small business moving a handful of applications might complete migration in 4 to 8 weeks. A mid-size organization with dozens of interdependent systems typically takes 3 to 9 months. The assessment and planning phase alone often takes 2 to 4 weeks. That time is well spent. Rushed planning is the most reliable predictor of a difficult cutover.

What is the difference between lift-and-shift and replatforming?

Lift-and-shift (Rehost) moves your application to the cloud with no changes to its code, configuration, or architecture. Replatforming makes targeted adjustments to take advantage of cloud services, for example moving a self-managed database to a managed cloud database service, without a full rewrite. Lift-and-shift is faster and lower risk. Replatforming delivers better performance and lower long-term operating costs.

What happens to my data during migration if something goes wrong?

If you’ve followed the pre-migration checklist, you have verified backups and a tested rollback plan before cutover begins. If data transfer fails mid-migration, you roll back to the on-premises environment and investigate the cause before trying again. Running checksums before and after each transfer phase lets you confirm data integrity without relying on visual inspection alone.

How do I know which workloads to migrate first?

Start with low-risk, non-production workloads: development environments, test systems, archived data, and internal tools. These let your team build familiarity with cloud operations before touching systems that affect customers or revenue. Save business-critical production workloads for last, when your team has completed at least one full migration cycle and has a validated rollback procedure ready.

What does on-prem to cloud migration cost?

Migration costs include one-time expenses like data transfer fees, migration tool licensing, and consultant time, plus the ongoing cloud subscription costs that replace your hardware budget. The most useful financial comparison is a total cost of ownership (TCO) analysis. Calculate your current annual spend on hardware, power, space, and IT labor, then compare it to projected cloud spend at your expected resource levels. Most cloud providers offer free TCO calculators to help you build that comparison before committing.