Every owner eventually faces a decision that feels too big to get wrong. Hire the second salesperson or wait. Sign the five-year lease or stay put. Take the big contract that needs $60,000 of upfront material. You run the numbers in your head, lose sleep, and eventually go with your gut. Scenario planning is the discipline that replaces that gut call with a set of answers you can actually look at: what happens to cash, profit, and payroll if the decision goes well, goes fine, or goes badly. It is the single most useful thing a CFO does for a business under $10M, and it takes an afternoon, not a finance degree.
According to the U.S. Bureau of Labor Statistics, roughly one in five new businesses does not survive its first year and about half are gone within five. Most of those closures are not caused by a bad product. They are caused by a decision that would have been survivable if someone had priced the downside first. This post shows you how to do that.
Key Takeaways
- Scenario planning means building three versions of the future (best, base, worst) for a specific decision and seeing what each does to cash and profit.
- You do not need special software. A copy of your 12-month forecast and three assumptions you can change is enough.
- The worst case is the one that matters most. If you can survive it, the decision is safe. If you cannot, you need a trigger and an exit plan before you commit.
- Every scenario should end with a number: the month cash bottoms out, and how low it goes.
- Decide the tripwires in advance. "If revenue is under X by month four, we do Y" is the difference between a plan and a hope.
What Scenario Planning Is (and What It Is Not)
Scenario planning is not predicting the future. It is admitting you cannot, then making sure the business survives the versions of the future you can imagine. Think of it as a stress test for a decision.
The three-scenario model
For any meaningful decision, you build three cases:
- Base case. What you realistically expect. This is usually your current forecast with the decision layered in.
- Best case. The decision works better than expected. Faster ramp, higher margin, quicker payback.
- Worst case. The decision underdelivers and you still carry the cost. The new hire produces nothing for six months. The contract pays 90 days late. The new location does half the projected volume.
What it is not
- It is not a budget. A budget is a single plan you hold yourself to. Scenarios are alternate futures you compare.
- It is not a spreadsheet exercise for its own sake. If a scenario does not change what you would do, it is not worth building.
- It is not pessimism. Building a worst case is how confident owners earn the right to be confident.
Start With Your Base Forecast
You cannot run a what-if without a "what is." Your starting point is a rolling 12-month cash flow forecast: monthly revenue, cost of goods, payroll, overhead, debt payments, owner draws, and the resulting ending cash each month. If you do not have one yet, build it first using our guide on how to build a 12-month cash flow forecast. It is the foundation for every scenario that follows.
Make sure the base case is honest
- Use trailing actuals, not aspirations, for revenue and margins.
- Include everything that leaves the bank, including loan principal and your own draw. Profit-only forecasts hide cash problems.
- Separate fixed costs from variable costs. Scenarios move variable costs with revenue; fixed costs stay put, which is exactly why they hurt in a downturn.
Once you trust the base case, save a copy. Every scenario is a copy of that file with a few cells changed.
Pick the Three Assumptions That Actually Matter
The mistake most owners make is trying to flex everything. That produces a model nobody understands. Instead, for the specific decision you are testing, identify the two or three assumptions that drive the outcome, and only move those.
Examples by decision type
- Hiring: ramp time to full productivity, revenue the hire generates per month at full speed, and fully loaded cost (salary plus taxes, benefits, and tools, typically 1.25 to 1.4 times base pay).
- New location or expansion: months to break even, monthly fixed cost added, and revenue per month at maturity.
- Big contract: upfront cash required, days until you are paid, and gross margin after the extra labor.
- Price increase: percentage of customers who leave, and the margin lift on those who stay. (Our post on how to price your services so every job is profitable covers the margin math.)
- Taking on debt: monthly payment, what the money produces, and how long it takes to produce it.
Set the range for each assumption
For each driver, write down three values: what you expect, a reasonable upside, and a reasonable downside. "Reasonable" matters. The worst case is not the business burning down; it is the decision simply not working while the costs stay. If a new salesperson normally takes four months to ramp, worst case is eight, not eighteen.
Run the Numbers and Find the Low Point
Now build the three copies of your forecast and read one line: ending cash by month.
What to look for in each scenario
- The trough. Which month does cash bottom out, and at what balance? This is the number that decides whether the decision is safe.
- The payback month. When does cumulative cash return to where it would have been without the decision?
- The gap to your floor. Compare the trough to the minimum cash you have decided never to go below. If you have not set that floor, our post on how much cash runway your business really needs walks through it.
A worked example
Say you are considering a $75,000 salesperson. Fully loaded, that is roughly $100,000 a year, or $8,300 a month.
- Base case: four-month ramp with little revenue, then $35,000 of new monthly revenue at 40% gross margin ($14,000 gross profit, or about $5,700 a month after the rep's cost). Cash dips about $33,000 over the ramp, then recovers around month ten.
- Best case: two-month ramp, then $45,000 monthly revenue ($18,000 gross profit). Cash dips about $17,000 and recovers by month four.
- Worst case: eight-month ramp, then $20,000 monthly revenue ($8,000 gross profit, which does not even cover the rep). Cash dips about $66,000 and never recovers on its own.
If your cash floor is $50,000 and you are sitting on $90,000 today, the base case is survivable, the worst case is not. That does not mean "don't hire." It means the hire needs a tripwire.
Set Tripwires Before You Commit
A scenario without a decision rule is just interesting. The real value of what-if planning is agreeing, in advance and in writing, what you will do if the worst case starts showing up.
How to write a tripwire
- Metric: one number you already track monthly. New revenue from the hire. Location sales. Days sales outstanding on the contract.
- Threshold: the value that signals you are on the worst-case path. Usually somewhere between base and worst.
- Deadline: the month by which the threshold must be met.
- Action: the specific thing you will do. Restructure the role. Renegotiate the lease. Stop taking similar contracts. Draw on the line of credit.
Written out, it reads: "If the new rep has not booked $10,000 of monthly revenue by the end of month five, we move them to an account-management role and pause the second hire." That single sentence protects the business from the most expensive thing an owner does, which is waiting one more month, six times in a row.
Review the tripwires monthly
Put them on the same page as your budget-vs-actual review. Our post on reading variance and acting on it covers the monthly rhythm. A tripwire nobody checks is not a tripwire.
Common Mistakes That Make Scenarios Useless
Building only the upside
If your best and base cases are the only ones that get real attention, you have written a sales pitch to yourself. Spend most of your modeling time on the worst case.
Flexing revenue but not timing
Many businesses die with a full order book because the cash arrives late. Every scenario should test collection timing, not just sales volume. A contract that pays in 75 days instead of 30 can turn a profitable job into a cash crisis.
Forgetting that costs arrive before revenue
New hires, new leases, and new equipment start costing money on day one. Revenue lags. Make sure the model reflects that lag rather than assuming both start together.
Treating the model as done
Assumptions age. Re-run the scenarios each quarter, or whenever a driver moves materially. The model you built in January is not the model you should decide with in September.
Doing it alone
The point of a scenario is to have your assumptions challenged. If nobody in your business pushes back on the ramp time or the margin, the numbers will confirm whatever you already wanted. This is a big part of what a fractional CFO does: bring an outside set of eyes that is paid to ask "and what if it doesn't?"
Conclusion
Big decisions do not have to feel like coin flips. Scenario planning turns "should we?" into "here is what happens if we do, in three versions, and here is the line we will not cross." Start with an honest 12-month forecast, pick the two or three assumptions that actually drive the decision, build best, base, and worst cases, find the month cash bottoms out, and write down your tripwires before you sign anything. Do that once and you will never want to make a major decision without it again. If you would rather have a CFO build and pressure-test the model with you, that is exactly what we do.