How to Calculate the Total Cost of Migrating an SME to the Cloud

Migration costs do not end when systems are moved

The cloud can change how a company pays for its infrastructure, but it does not automatically guarantee savings. To make an informed decision, an SME needs to compare the total cost of ownership (TCO) of keeping its current systems with that of one or more cloud scenarios over the same period. The comparison should include both the migration project and subsequent operations, not just the estimated cost of servers.

The result depends on the applications, their usage patterns, the volume of data, the work required to adapt them, and the terms of the contract. For this reason, generic estimates can serve as a guide, but they do not replace the company’s own data.

1. Establish a reliable baseline

Before projecting future spending, it is useful to inventory what exists and how much it costs today. The record should link applications and workloads to the infrastructure they use, their capacity requirements, and the services that support them. It is also useful to identify contracts, equipment, or data centers whose expiration dates could affect the migration schedule.

The baseline should not be limited to the purchase of servers. Depending on the current model, it may include maintenance, hosting, energy, storage, backups, licenses, management tools, and staff time spent operating the environment. Where possible, it is preferable to use actual costs and utilization data—not just installed capacity—to avoid comparing infrastructure sized for peak demand with a cloud estimate based on average usage.

This reference will make it possible to measure later whether spending has changed and which items explain the difference. If current costs are omitted or costs that will continue are attributed to the project, the comparison loses consistency.

2. Separate migration costs from operating costs

For each alternative, organize costs into two categories. The first covers the migration project: assessment and planning, tools, specialist services, internal team effort, testing, application changes, and data preparation. The second covers recurring expenses once the workloads are operational.

Internal labor also counts. It does not always mean hiring additional staff, but it does consume time that could be devoted to other tasks. A practical estimate is to identify which roles will participate, what activities they will perform, and how much time they will spend; that effort can then be valued using a method consistent with the company’s budget.

The chosen method changes the cost profile. A move with few changes may require less initial work but preserve an inefficient configuration in the cloud. Adapting or redesigning an application may increase the project’s effort and duration while enabling managed services or other architectural options. There are also intermediate alternatives, such as moving first and optimizing components later. No path alone guarantees a lower total cost: each workload must be modeled individually.

3. Project the cloud bill using actual usage patterns

In the cloud scenario, calculate separately the resources expected to be consumed, such as compute, memory, and storage, and complementary services. A provider’s published rate is not the same as the full cost: the estimate depends on the selected configuration, actual consumption, and applicable commercial terms.

Also include databases, backups, monitoring, support, and administration or security tools, whether they are provided by the provider or by third parties. Review existing software licenses: they may change when a workload is moved, and some tools may be shared between on-premises and cloud environments. Do not count a license or contract as a saving if the company will not actually be able to cancel it.

Data movement deserves its own line item. There may be costs when transferring information to the cloud environment and, depending on the provider and destination, when taking it out or moving it between regions or platforms. The amount depends on the volume and frequency of transfers; if that data is not yet clear, document the uncertainty and model different assumptions rather than presenting a figure as definitive.

4. Account for coexistence and security

During a transition, it may be necessary to keep both the old and new systems running at the same time. This period of parallel operation may involve duplicate infrastructure, licenses, support, and additional work. Its duration will depend on the plan and validation requirements, so it should be included in the financial timeline for each scenario.

Security does not disappear after migration either. The provider and the customer may have different responsibilities, so the company should identify which controls and tasks it will continue to manage: for example, access configuration, data protection, monitoring, and operational response. Add the relevant tools, services, and staff hours. Do not automatically attribute all security costs or responsibilities to the provider.

5. Compare scenarios over a common time horizon

Choose a period that reflects the workloads’ typical use and relevant variations, such as seasonal changes. For each alternative, apply the same duration and business assumptions. It is also useful to separate the initial setup period: the first few months may include adjustment tasks and expenses that do not represent stabilized operations.

A simple structure for the calculation is:

A cloud exit deserves its own estimate. If data or services are moved to another provider or to the company’s own infrastructure in the future, transfer costs, tools, technical work, and parallel operations may arise. It is not possible to determine this cost without knowing the data volume, architecture, and contractual terms; it can be treated as an assumption and updated when comparing offers.

A table for organizing the estimate

Validate the model and review its assumptions

The comparison is more valuable when each item is supported by verifiable data and labeled as an observed cost, estimate, or assumption. For cloud consumption, providers’ calculators can help build scenarios, but their results should be checked against the inventory, expected utilization, and specific contracting terms.

Rather than relying on a single forecast, it can be useful to compare consumption and migration alternatives: for example, moving an application with few changes versus adapting it, or considering stable versus variable usage. The goal is not to predict a future bill exactly, but to understand which decisions affect the cost and how much the conclusion depends on assumptions that remain uncertain.

Finally, review the calculation when consumption, architecture, licenses, or the schedule changes. An initial estimate is a basis for decision-making and planning, not a guarantee of savings. The most useful comparison for the company is one that transparently shows what is included, for how long, and under what conditions.