Choosing the best server migration company for SaaS startups moving to AWS is a different problem from choosing a generic hosting partner. Your customers are logged in right now, your database is changing every second, and your team is small enough that a bad cutover can consume a whole sprint. This guide compares the main types of provider, explains what a safe AWS migration actually involves, and gives you criteria to judge any proposal. It is written for founders and engineering leads who are moving from a VPS, shared hosting or another cloud.
We do not quote prices here, because they depend on your stack and data volume. Use this article to shape your questions, then request an itemised quote. If you want to see how we scope this kind of project, our server migration service page explains the process.
What a SaaS migration to AWS really involves
Moving files is the easy part. A SaaS product has state in many places, and each one has to arrive intact and in sync. A credible provider will talk about all of the following before they talk about tools.
- The primary database: relational data, replication lag, schema changes in flight and long-running transactions.
- Object and file storage: user uploads, exports and generated reports that may live on local disk today.
- Background workers and queues: jobs that must not run twice or get lost during the switch.
- Secrets and configuration: API keys, webhooks, environment variables and third-party allow-lists tied to your old IP address.
- Email and outbound reputation: sending from a new IP can affect deliverability if it is not planned.
- Customer integrations: clients who whitelist your IP or hard-code endpoints.
Database cutover: the step that decides success
For most SaaS products the database is the hard part. There are two broad approaches, and the right one depends on how much downtime your customers will accept.
Dump and restore
You freeze writes, export the data, import it into the new database and switch traffic. It is simple and easy to verify, but the downtime window grows with the size of your data. This suits early-stage products with modest databases and a tolerant user base, ideally scheduled outside the hours your customers work.
Replication and promotion
You build the new database as a replica of the old one, let it catch up, then briefly pause writes, confirm the replica is fully in sync and promote it. Downtime shrinks to the time it takes to switch, but setup is more involved. You need network access between environments, matching database versions or a tested upgrade path, and a clear check that nothing was missed. AWS offers managed tooling for this, yet the tooling does not decide your cutover order, your verification queries or your rollback trigger. Those need an experienced person.
Whichever route you take, ask the provider how they will prove the data matches. Row counts, checksums on critical tables and a smoke test of key customer workflows are reasonable expectations.
DNS TTL and traffic switching
DNS is where many migrations quietly go wrong. Records are cached by resolvers around the world for the duration of their time-to-live, so a change does not reach everyone at once. A sound plan lowers the TTL on the relevant records well ahead of the cutover, so the switch propagates quickly, and raises it again afterwards once things are stable.
Also ask about the following.
- Whether the old server will keep forwarding or proxying requests to the new one while stragglers still resolve the old address.
- How API clients and mobile apps with cached addresses will be handled.
- Whether TLS certificates are issued and tested on the new environment before the switch.
- Who owns the DNS accounts and can make changes quickly during the window.
When our team plans a move, we treat DNS and certificates as a rehearsal item, not a last-minute task. You can see the wider approach on our server migration company page.
Staging rehearsal before the real cutover
The most reliable predictor of a calm migration day is whether the team has already done it once. A rehearsal means building the AWS environment, restoring a recent copy of production data into it and running the application against it, with real configuration but no live traffic.
A good rehearsal answers practical questions: how long does the data copy take, which services fail on first start, which hard-coded paths or hostnames were forgotten, and does performance match expectations under a realistic load test. It also gives you an honest estimate of the downtime window instead of a guess. Be cautious of any provider who proposes to skip rehearsal for a production SaaS system.
Handle personal data carefully during rehearsal. If you use a production copy, keep it in a locked-down environment and delete it afterwards, or mask sensitive fields where your obligations require it.
Rollback plan: decide it before you start
A rollback plan is not pessimism. It is what lets you proceed with confidence. Before the migration window opens, agree in writing what conditions trigger a rollback, who makes the call and how long you will wait before making it.
- Keep the old environment intact and untouched until the new one has run cleanly through at least one full business cycle.
- Decide how writes are handled if you roll back after customers have created data on the new side. Without a plan, you can lose or duplicate records.
- Keep DNS changes reversible by retaining the old records and a low TTL until you are satisfied.
- Take verified backups of the source immediately before cutover and test that a restore works.
- Define go and no-go checks such as login, payment flow, key API calls and background job processing.
Downtime windows and customer communication
Your downtime window should reflect when your users are least active, and your communication should be honest and early. Pick a window based on your own usage patterns, not a generic late-night slot, since a B2B product used across time zones may have a quiet period that is not what you expect. Notify customers in advance, publish a status page, and tell support what to say if someone writes in mid-cutover. A provider who plans the technical steps but leaves communication to chance is leaving half the job undone.
Where AWS cost surprises come from
Many startups find that the migration itself is manageable and the bill afterwards is the surprise. We will not give figures, but these are the areas worth discussing before you commit.
- Data transfer: traffic leaving AWS to the internet or to another provider is typically charged, and a chatty architecture can add up.
- Overprovisioned instances: copying your old server size one-to-one often wastes money, while undersizing causes slow performance.
- Managed database choices: instance class, storage type, replicas and backup retention all affect the monthly cost.
- NAT gateways and networking: private subnets that reach the internet can carry ongoing charges that are easy to overlook.
- Idle resources: forgotten test environments, unattached volumes and old snapshots keep billing.
- Dual running: you pay for both environments during the overlap period, so a long overlap has a real cost.
- Support and monitoring tools: logging volume, monitoring and paid support plans add to the total.
Ask any provider for a projected monthly run cost for the new environment alongside the migration quote, along with the assumptions behind it. Set up billing alerts on day one.
Comparing the types of migration provider
There is no single best option for every startup. The table below compares the usual choices on the factors that matter for a SaaS move to AWS.
| Provider type | Best for | Strengths | Watch out for |
|---|---|---|---|
| Your own engineers | Teams with prior AWS experience and spare capacity | Deep product knowledge and full control | Slows feature work; first-time mistakes land on production |
| Specialist migration company | Startups that want a planned, rehearsed move without hiring | Repeatable process, rehearsal, rollback planning, time-boxed project | Needs a clear scope and good documentation handover |
| AWS partner or reseller | Teams who want billing, support and credits through one party | Close AWS relationship and programme access | May steer you to AWS-only choices and their own add-on services |
| Freelancer or contractor | Small, simple stacks with a limited budget | Flexible and often lower cost | Single point of failure, limited cover during cutover and afterwards |
| Large consultancy | Complex estates with compliance and procurement requirements | Broad capability and formal governance | Heavier process and cost, often more than a startup needs |
| Managed hosting provider | Teams who want ongoing operations, not just a move | Continuous monitoring and support after migration | Possible lock-in to their tooling and contract terms |
For many startups, a specialist company or a hybrid, with your engineers owning the application and an outside team owning the infrastructure move, offers the best balance of speed and risk.
How to evaluate a proposal
Whichever type you pick, test the proposal against these questions.
- Do they ask about your database size, write patterns and acceptable downtime before quoting?
- Is a staging rehearsal included as a named deliverable?
- Is there a written rollback plan with clear triggers?
- Is the quote itemised so you can see assessment, build, rehearsal, cutover and post-migration support separately?
- Will you own the infrastructure code, diagrams and runbooks at the end?
- Does AWS access stay in your own account, with the provider using limited, revocable permissions?
- What support do you get in the days after cutover, when issues are most likely to surface?
If you want a second opinion on a quote you already hold, our Linux and Windows server migration team is happy to review it with you.
Why Companies Choose CloudHouse for Server Migration
Clients come to CloudHouse because we plan delivery in clear stages, rehearse the move before touching production and stay available for support after launch. Our quotes are transparent and itemised, so you can see what each phase involves before you agree to it. Whether your workloads run on Linux or Windows, the aim is a migration your customers barely notice.
Conclusion
The best server migration company for a SaaS startup moving to AWS is the one that treats your database cutover, DNS plan, rehearsal and rollback as first-class deliverables, and that is honest about downtime and ongoing cost. Compare provider types against your team capacity and risk tolerance, ask for itemised quotes, and insist that your AWS account and documentation stay yours. To discuss your move and receive a clear proposal, visit our server migration services page and request a quote.
