Do you need a CFO, or a finance function?

Somewhere past a hundred employees, the finance conversation changes. The bookkeeper who has been with you since the start is stretched. The board wants a forecast, not a bank balance. A lender or investor asks a question nobody can answer inside a week. The usual response is to start a CFO search.

It is worth pausing before you do. A full-time CFO at this stage is expensive, hard to hire well, and frequently under-used. The more common problem is not a missing executive. It is a missing function: the systems, the close, the controls, the reporting rhythm that a CFO would expect to find already in place.

What a CFO actually does all day

Strip the title back and a CFO's week divides into three kinds of work. The first is judgement: pricing, cash, capital, the commercial calls that shape the business. The second is oversight: making sure the numbers are right, on time, and understood. The third is infrastructure: building and fixing the systems and processes that produce those numbers in the first place.

In a business of a few hundred people, the first category is perhaps a day a week. The second is a few days a month, clustered around the close. The third is a project, not a job. Hire a full-time CFO into that environment and you either pay an executive salary for operational work, or you watch a senior person spend their first year building the foundations they should have inherited.

The function comes first

A finance function that works has a few recognisable parts, whatever the size of the company.

• A ledger that is structured for how the business is actually run, not how it looked five years ago.
• A month-end close that finishes inside a known number of working days, every month, with a checklist.
• Controls over money leaving the business: approval flows, segregation of duties, reconciled bank accounts.
• Management accounts that answer the questions leadership is asking, with commentary.
• A rolling forecast and a short-term cash view that are updated, not rebuilt, each month.

None of this requires a CFO to be present forty hours a week. It requires someone senior to design it, a competent team to run it, and a regular rhythm of review. That is the fractional model in one sentence.

When the full-time hire is right

There are clear triggers for a permanent CFO: an imminent institutional fundraise, a sale process, multi-entity complexity with real treasury work, or a scale where finance leadership is a full-time job by any measure. The honest advice is that most businesses in the 100 to 1,000 employee range hit those triggers later than they think, and are better served arriving there with a working function and a clean set of numbers.