You can move a 50-to-100-person professional services firm to the cloud without losing a single billable hour, provided you migrate in phases rather than all at once. This cloud migration guide sets out the sequence that works audit what you run, classify data against your compliance obligations, move low-risk workloads first, pilot with one team, then cut over the practice-critical systems out of hours with a tested rollback plan. Most firms of this size complete the process in three to six months. The technical work is rarely the hard part. The risk sits in the discovery stage, where undocumented line-of-business applications, expiring software licences and unclear data residency requirements surface late and stall everything behind them. Get discovery right and the rest is scheduling.

Who This Is For

This is written for operations directors, practice managers and finance leads in professional services firms with 50 to 100 staff. Think accountancy practices, law firms, consultancies, architecture studios and recruitment businesses. You have grown past the point where a single on-premises server in the comms cupboard is sensible, but you are not big enough to carry a dedicated infrastructure team. Typically, you have an ageing server approaching refresh, a practice management or case management system that everything depends on, hybrid working that IT was never designed for, and a professional indemnity insurer or regulator asking increasingly specific questions about where client data lives.

Why Migration Stalls in Firms Like Yours

The blocker is almost never the technology. It is that nobody can afford to be the person who took the fee earners offline during month-end. Firms tell us the same things: “we cannot risk the case management system”, “our year-end is January so that is out”, “the last supplier quoted a number and then it doubled”. There is also the application nobody owns, the twelve-year-old bespoke tool one partner relies on, which turns out to be incompatible with anything modern. Add unclear licensing costs and a quote written in language no one internally can challenge, and the project quietly slips another quarter.

If you are weighing up a server refresh against a move to the cloud, a short discovery session will tell you which makes commercial sense. Book a cloud assessment →

How to Use This Cloud Migration Guide in Practice

Treat migration as a business change programme with a technical component, not an IT project. That distinction matters because the decisions that derail firms are commercial ones: which systems justify the cost of re-platforming, which are due for replacement anyway, and which can be left alone for now. Our approach starts with a fixed-scope assessment rather than a proposal, so you see the estate, the dependencies and the true monthly running cost before any migration work is quoted.

We are deliberately vendor-neutral on the destination. Microsoft 365 and Azure suit most professional services firms because of the identity and compliance tooling, but a hybrid model, keeping one regulated workload on-premises, is often the right answer for two or three more years. This cloud migration guide assumes you want an evidenced recommendation, not a preference dressed up as best practice. Every recommendation we make comes with the cost, the risk and the alternative written down.

Building an SME Cloud Strategy That Fits Your Compliance Position

Your SME cloud strategy has to start with your regulator, not your infrastructure. Solicitors answer to the SRA, accountants to the ICAEW or ACCA, and everyone to UK GDPR. Each imposes expectations about data residency, meaning the country your client data physically sits in, and about retention periods.

Before you move anything, classify your data into three tiers: client-confidential and regulated, internal-commercial, and general. Regulated data should guide the region you select, the encryption standard and the backup retention you pay for. General data can go anywhere cheap. Firms that skip this step usually over-engineer the whole estate and pay premium rates to protect the marketing folder. Getting the classification right is what makes a business cloud transition affordable.

Step by Step: The Six-Stage Migration Sequence

Audit the full estate. Document every application, server, integration, licence renewal date and who owns it. Include the shadow tools departments bought on a company card. Expect this to take two to three weeks and to surface at least one surprise.

Classify data and confirm compliance requirements. Map each data type against your regulator’s expectations, then fix the target region and retention policy. Get this signed off by whoever carries the compliance risk.

Sequence the workloads. Move email, file storage and collaboration first because they are well understood and easily reversed. Leave the practice management system until you have proven the process.

Pilot with one department. Choose a team of eight to twelve people, run them fully in the new environment for two weeks and log every issue. Fix the issues before anyone else moves.

Migrate in waves with a rollback plan. Schedule cutovers for Friday evenings, keep the old system live and readable for 30 days, and test the restore before you switch, not after.

Decommission and optimise. Turn off the old servers, cancel the redundant licences and review your consumption at 30 and 90 days.

What to Watch Out For

Lift-and-shift pricing traps. Moving a badly configured server to the cloud unchanged usually costs more to run than it did on-premises. Right-size before you migrate.

Ignoring licence entitlements. Some line-of-business software is licensed per physical server and becomes expensive or non-compliant in a virtual environment.

Migrating during peak season. Avoid year-end, tax deadlines and matter-heavy periods entirely.

Assuming backup is included. Cloud platforms replicate data, they do not protect it from deletion or ransomware. Budget for a separate backup.

No named internal owner. Projects without a decision-maker inside the firm drift.

Quick Checklist

• List every application and its licence renewal date.
• Identify the single system the firm cannot operate without for a day.
• Confirm your regulator’s data residency and retention requirements in writing.
• Get a 12-month running cost estimate, not just a migration price.
• Agree the pilot team and the two-week test window.
• Confirm the rollback plan and test a full restore before cutover.
• Set the decommissioning date for the old hardware.
• Diarise a 90-day cost and performance review.

Frequently Asked Questions

How long does cloud migration take for a 50-to-100-person business? Typically, three to six months from assessment to decommissioning. Discovery and planning take four to six weeks, the pilot two weeks, and the migration waves run over six to ten weeks depending on how many line-of-business applications you have. Firms with a single practice management system and no bespoke software often finish faster.

Is cloud cheaper than replacing our on-premises server? Not automatically, and any supplier who says otherwise has not looked at your estate. Cloud shifts capital expenditure to a predictable monthly operating cost and removes refresh cycles, but poorly configured workloads can cost more month on month. Compare five-year total cost, including hardware, licensing, power, backup and the staff time you currently spend on maintenance.

Can we keep some systems on-premises? Yes, and many regulated professional services firms should. A hybrid model lets you move email, files and collaboration while keeping one sensitive or awkward application in place until it is due for replacement. This is often the cheaper and lower-risk route.

Will staff lose access to files during the migration? They should not. Properly sequenced cloud migration steps run cutovers outside working hours, keep the source system readable for at least 30 days and migrate department by department. Any supplier proposing a single weekend big-bang for a firm your size is taking a risk on your behalf.

You are likely at one of two decision points: a server warranty expiring in the next twelve months, or a compliance question you cannot currently answer with confidence. Both have a deadline attached, and both get more expensive the longer they sit. The firms that migrate well are not the ones with the biggest budgets. They are the ones that spent four weeks on discovery before signing anything, and that knew exactly which system they could not afford to lose. Work out that answer now, while you still have the option of doing this on your own timetable rather than a supplier’s.

Ready to see what your migration would involve and cost?

Arrange a no-obligation cloud assessment → and you will leave with a documented estate, a phased plan and a twelve-month cost projection.