A fractional CFO gives a startup senior financial leadership for part of the week or month, without adding a full-time executive. The work is forward-looking: deciding how long cash lasts, what a hiring plan does to runway, which metrics belong in an investor update, and what the board needs to see before a decision. It is different from bookkeeping, which records and reconciles what already happened.
For most startups, the useful question is not whether a CFO sounds impressive. It is whether the company now has financial decisions that are too consequential, frequent, or complex for the founder to handle with a spreadsheet and occasional help from an accountant.
What does a fractional CFO do for a startup?
A fractional CFO owns the financial decision system. The exact scope changes with stage, but the recurring work usually includes:
- building and maintaining a cash forecast
- modeling hiring, pricing, fundraising, and growth scenarios
- defining the metrics used by founders, investors, and the board
- preparing board and investor reporting
- helping plan a financing process and answering diligence questions
- setting budgets and comparing actual results with the plan
- translating accounting results into operating decisions
- coordinating the bookkeeper, tax preparer, payroll provider, and other finance specialists
A good fractional CFO does not merely send reports. They explain what changed, why it changed, and which decision follows from it. If revenue is growing while cash is shrinking faster, the answer might be slower collections, annual software renewals, a hiring wave, or gross margin pressure. The CFO's job is to isolate the driver and show the founder what happens under each available choice.
Fractional CFO vs bookkeeper vs accountant
These roles solve different problems, and a startup often needs more than one.
| Role | Primary question | Typical work |
|---|---|---|
| Bookkeeper | What happened? | Categorization, reconciliations, close, financial statements |
| Accountant or controller | Are the records complete and correct? | Accruals, controls, reporting quality, close management |
| Fractional CFO | What should we do next? | Forecasting, planning, fundraising, board reporting, decisions |
| Full-time CFO | Who owns finance every day? | The same strategic work, plus continuous executive leadership and team management |
The order matters. Forecasts built on unreconciled cash or incomplete revenue are polished guesses. Before paying for CFO time, make sure the startup bookkeeping system produces dependable statements and a consistent close. Median keeps transactions categorized and posted every business day, with an accountant reviewing exceptions, so an outside CFO can spend time on decisions instead of rebuilding the ledger.
When should a startup hire a fractional CFO?
There is no universal revenue or funding threshold. The right time arrives when the cost of a wrong financial decision is greater than the cost of better analysis. These are the clearest triggers.
You are preparing to raise capital
A financing process creates questions about runway, use of funds, hiring plans, dilution, milestones, and the relationship between growth and cash. A fractional CFO can turn those assumptions into one model, pressure-test them, and keep the numbers consistent across the deck, data room, and investor conversations.
Your runway answer changes depending on who asks
Runway should come from one forecast with named assumptions, not from bank balance divided by last month's burn. If the founder, bookkeeper, and board each produce a different answer, the company needs one owner for the model. Our guide to startup runway explains the basic calculation and where it breaks.
The board wants reporting the team cannot produce reliably
A board pack should reconcile to the books and explain movement against plan. If every meeting starts with a rush to rebuild revenue, burn, headcount, or cash metrics, a fractional CFO can define the package and make the preparation repeatable. Use this board financial package guide to see what belongs in it.
Hiring and spending decisions have become linked
At an early stage, one hire can materially change runway. Once the company is comparing several hires, vendor commitments, and growth investments at the same time, each decision needs to sit inside the same forecast. This is where scenario planning becomes more useful than a static annual budget.
The founder is spending executive time rebuilding finance work
A founder should understand the model, but should not have to repair formulas before every investor call. If finance preparation repeatedly displaces customer, product, or hiring work, fractional ownership can be cheaper than continuing to use founder time as the control system.
Revenue is growing but cash is harder to explain
Growth can make cash less intuitive. Annual contracts, deferred revenue, slow collections, payment terms, inventory, or rising delivery costs can separate booked revenue from bank movement. A fractional CFO connects the income statement, balance sheet, and cash forecast so the team can see where cash is actually tied up.
What should be included in fractional CFO services?
The engagement should name deliverables, cadence, and decision rights. A useful scope often includes:
- A rolling cash forecast. Usually 13 weeks for near-term liquidity, plus a monthly model that reaches through the fundraising or operating horizon.
- Budget and scenario models. Base, upside, and downside cases tied to hiring, revenue, gross margin, and financing assumptions.
- A monthly decision package. Actuals against plan, cash, runway, key operating metrics, and a short explanation of the important changes.
- Founder and board meetings. A set cadence for interpreting the numbers and deciding what changes.
- Fundraising support when needed. Model preparation, data-room consistency, investor questions, and diligence coordination.
- Finance team coordination. Clear ownership across bookkeeping, tax, payroll, and legal providers.
Ask what is not included. Tax return preparation, audit work, legal advice, payroll administration, and daily bookkeeping are often separate services. A vague promise of “strategic finance” without named outputs makes it difficult to know whether the engagement is working.
How much do fractional CFO services cost?
There is no standard rate card for the market. Public guides from providers commonly show monthly retainers ranging from a few thousand dollars to well into five figures, depending on stage, transaction complexity, fundraising support, meeting cadence, and whether a team is included. Hourly and fixed-project arrangements also exist.
Use the scope rather than the headline rate to compare proposals. One provider may include a model, board package, weekly meeting, and fundraising support. Another may quote a lower retainer for a monthly call and charge separately for each project. Ask each candidate to price the same written deliverables.
The cleanest comparison is:
[ \text{Monthly cost} = \text{recurring scope} + \text{project work} + \text{underlying accounting work} ]
That final term is easy to miss. Some fractional CFOs require the startup to bring its own bookkeeper. Others bundle a finance team. If the books are late or need cleanup, senior advisory hours may be consumed by basic accounting before forecasting begins.
Median does not sell fractional CFO services on this page. Median provides the current bookkeeping and reporting layer that founders and outside CFOs use. For companies under $1 million in annual revenue, Median's published bookkeeping prices are $200 per month under $250,000 and $500 per month from $250,000 to $1 million. Companies above $1 million are scoped based on the work required. A fractional CFO's fee is separate and set by that advisor.
Fractional CFO vs full-time CFO
A fractional CFO fits when the company needs senior judgment but not a full executive workload. A full-time CFO fits when financing, capital allocation, risk, team leadership, and cross-functional planning require daily ownership.
| Question | Fractional CFO | Full-time CFO |
|---|---|---|
| Time commitment | Part of the week or month | Full-time executive role |
| Best fit | Defined strategic needs and limited recurring load | Continuous complex decisions and a finance team to lead |
| Hiring speed | Usually faster | Longer executive search and onboarding |
| Cost structure | Retainer, hourly, or project | Salary, benefits, bonus, and often equity |
| Continuity | Depends on contracted capacity | Dedicated to one company |
Do not treat fractional as a permanently cheaper substitute when the role has become full-time. Warning signs include a growing finance team with no daily leader, frequent financing or acquisition work, several entities or countries, and executives who need the CFO in operating meetings throughout the week.
What does a startup need at each stage?
Pre-seed
Most pre-seed companies need clean books, a simple runway model, tax readiness, and help deciding how much to raise. A recurring CFO engagement may be unnecessary unless the business model or financing is unusually complex. A focused project can be enough.
Seed
At seed, hiring plans and investor reporting become recurring. This is the stage where a monthly fractional engagement often starts to make sense: maintain the forecast, compare actuals with plan, prepare investor updates, and help the founder evaluate tradeoffs.
Series A and beyond
The work typically expands into departmental budgets, board reporting, revenue and margin analysis, controls, and finance-team design. The company may still use a fractional CFO, but it should review regularly whether the workload now requires a full-time leader.
Stage is a guide, not a rule. A bootstrapped company with several products, complex margins, and tight cash may need CFO-level help before a simple venture-backed company at the same revenue.
How to choose a fractional CFO
Interview for the decisions the person has handled, not the industries listed on a profile.
- Ask for an example of a cash decision they changed and what evidence changed it.
- Ask who builds and maintains the model after the first version.
- Ask how the forecast ties back to the monthly books.
- Ask what arrives before each board meeting and how far in advance.
- Ask how much capacity is guaranteed and who covers an absence.
- Ask which work is performed by the named CFO and which goes to junior staff.
- Ask for references from companies at your stage and with your business model.
- Put the first 90 days, recurring deliverables, and exit terms in writing.
A strong candidate should also be comfortable saying that you are too early. If the immediate problem is unreconciled accounts, missing statements, or a close that takes six weeks, the first investment should usually be fixing the accounting foundation.
How bookkeeping and fractional CFO work fit together
The CFO layer is only as current as the records beneath it. The handoff works best when the bookkeeper owns transaction processing and reconciliations, the accountant owns close quality, and the fractional CFO owns planning and decisions. Each person should know which questions move across the boundary.
Median is built to sit under that advisory relationship. We keep the books current every business day, provide reviewed statements, and work with the advisor the founder already trusts. Fractional CFOs can also partner with Median when a client needs a stronger bookkeeping layer or when a founder is still below the advisor's minimum.
The practical next step
Start by writing down the next three financial decisions the company must make. If they are mostly about categorizing transactions, closing the books, or preparing a tax return, fix the accounting layer first. If they are about how much to raise, when to hire, which plan protects runway, or what the board should approve, interview fractional CFOs against those exact decisions.
Before the first call, bring the latest balance sheet, profit and loss statement, cash balance, headcount plan, and current forecast. The quality of the conversation will improve immediately because the candidate can diagnose the decision system rather than guess at the state of the books.
If you need the accounting foundation first, talk with Median. If the books are ready and the problem is strategic, use the questions above to find a fractional CFO whose experience matches the next stage of the company.