If you want a cloud migration to go smoothly, the most important work happens before anything moves. A cloud migration assessment is how you avoid the classic problems: hidden dependencies, security gaps, unexpected downtime, and cloud costs that spiral because nobody set guardrails.
The goal is to make clear decisions: what to migrate first, what to modernise, what to retire, and what your platform must have in place, so the business doesn’t pay for your learning curve.
This post covers what you should measure in a cloud migration assessment, how those measurements translate into a cloud migration roadmap. At the end, you’ll also get access to a practical checklist you can use internally.
Before you move anything to the cloud, measure the eight things that decide whether migration is smooth or painfully expensive, from business criticality and dependencies to security, operating model readiness, and cost governance.
Contents
(Click on a headline to jump to the relevant section)
What Is a Cloud Migration Assessment?
What Should I Measure Before I Move to the Cloud?
Why Should I Carry Out a Cloud Platform Readiness Assessment?
Turning Measurement Into a Cloud Migration Roadmap
What Mistakes Are Driving Up Cloud Migration Costs?
Cloud Migration Assessment Checklist (With Download)
Next Step: Book a Cloud Migration Assessment
What Is a Cloud Migration Assessment?
A cloud migration assessment is a structured evaluation of your applications, infrastructure, data, security, and operating model to determine:
- which workloads you can migrate now
- what risks and constraints you need to address first
- what your target platform must provide (governance, security, resilience, operations)
- how to sequence the work into a realistic plan
It’s closely linked to a cloud platform readiness assessment, which focuses on whether your target environment is ready to host production workloads safely and consistently.
What you’ll get the end of a cloud migration assessment? Choices, priorities, and a defendable plan you can take to the board.
What Should I Measure Before I Move to the Cloud?
(Click to expand)
Why Should I Carry Out a Cloud Platform Readiness Assessment?
A cloud platform readiness assessment is the platform side of the equation. Even if your applications are ready, only a prepared platform ensures consistent security, operational control and a governed, standardised cloud estate.
At minimum, assess readiness across:
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Identity and access: role-based access, MFA, privileged access controls
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Network and connectivity: segmentation, routing, DNS, firewalling, connectivity to on-premise and third parties
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Security guardrails: baseline policies, logging standards, vulnerability expectations
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Monitoring and operations: alerting, log retention, runbooks, escalation paths
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Backup and Disaster Recovery: defined recovery approach and tested processes
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Governance: naming conventions, tagging standards, resource provisioning rules, cost controls
These basics ensure you stick to your migration timeline and don’t spend months cleaning up after it, especially if you managed to do it quicker than would usually be expected (= do it right or do it twice).
Turning Measurement Into a Cloud Migration Roadmap
This is where the assessment pays off. Your measurements should translate into a cloud migration roadmap that the business can understand and support. Actionable (concrete) output means you should be able to start the first wave (0) confidently.
A credible roadmap includes:
1. Prioritisation: value vs risk vs effort per workload
2. Wave plan: sequencing that respects dependencies and business criticality
3. Migration approach: rehost/replatform/refactor/retire/retain decisions
4. Platform tasks: what must be built first to host workloads safely
5. Risk register: known risks and mitigations, with named owners
6. Operating model readiness: what support and process changes are required
7. Timeline and milestones: realistic and measurable, not optimism
What’s Your End Goal?
If you’re buying or running a cloud migration assessment, you should expect to come out with:
- A prioritised application list with rationalisation decisions
- Dependency maps for key systems (at least for early waves)
- Workload placement guidance (where each workload fits best based on requirements)
- Platform readiness gaps and a plan to close them
- Security and compliance requirements per workload
- A wave plan and migration approach for the first phases
A roadmap with clear milestones, risks, and ownership.
What Mistakes Are Driving Up Cloud Migration Costs?
In a nutshell– an inventory that’s too high-level, forgetting about your baseline numbers, not involving all stakeholders, a lack of concrete prioritisation, and not planning for the all-important migration aftercare.
Our list in full:
- Inventory without dependencies: while this look tidy, it fails to show the big picture
- Security engaged too late: results in late rework or go-live delays
- No baselines: you can’t prove success or diagnose regressions
- Ignoring vendors and licensing: turns into last-minute blockers
- No operating model planning: support collapses post-migration
- Vague prioritisation: everything becomes urgent, so work volume increases, and nothing moves cleanly
Cloud Migration Assessment Checklist
Use this as a quick readiness check. If you can’t answer these confidently, you’re not ready to move anything significant.
Application and Business
- Do we know what the application does and who owns it?
- Are availability, performance, Recovery Time Objective/Recovery Point Objective requirements defined?
- Are key business dates and change windows agreed?
Dependencies and Integration
- Have we mapped upstream/downstream dependencies?
- Do we understand authentication and identity dependencies?
- Do we know how data flows in and out (APIs, files, batch)?
Technical Readiness
- Are OS, database, and runtimes supported and patchable?
- Do we know whether it’s rehost/replatform/refactor/retire/retain?
- Are vendor support and licensing constraints confirmed?
Data and Security
- Is data classified, and are residency/retention requirements known?
- Are encryption, logging, and access controls defined?
- Is vulnerability management and incident response ready for the new environment?
Platform Readiness
- Are identity, network, and security guardrails in place?
- Are monitoring, backup, and DR processes designed and tested?
- Are governance and cost controls (tagging, budgets) defined?
Operations and Support
- Who supports it after migration, and do they have runbooks?
- Is hypercare planned with clear staffing and escalation routes?
- Is the service desk prepared with knowledge articles and triage guidance?
Cost and Optimisation
- Do we have a cost baseline and an optimisation approach?
- Have we identified likely cost traps (oversizing, egress, always-on)?
- Are guardrails in place to prevent uncontrolled spend?
Next Step: Book a Cloud Migration Assessment
If you want a migration plan that doesn’t rely on guesswork, a cloud migration assessment is the most sensible first move. It gives you the measurements, decisions, and a clear cloud migration roadmap to sequence work safely.
Book a cloud migration assessment to get clarity on: what to migrate first, what your platform must support, and how to run early migration waves without disrupting the business.
