Scenario planning: a base case, an upside, and the bad one

A single forecast is a guess wearing a suit. You build one tidy spreadsheet, the numbers march neatly to the right, and you treat it as the future. Then reality shows up — a deal slips, a hire takes three months instead of one — and the whole plan buckles because you only ever modeled the world where everything went right.

The fix isn't a smarter guess. It's building three. A base case, an upside, and a downside turn one fragile prediction into a plan you can actually steer with. This is the heart of FP&A — Financial Planning & Analysis, the work of connecting your numbers to the decisions in front of you.

Done well, scenario planning doesn't take a week or a finance degree. It takes honesty about the two or three things that truly move your business, and the discipline to decide your responses before you're under pressure.

Three cases, not three spreadsheets

The mistake people make is rebuilding the whole model three times. You don't need to. A good scenario set flexes only the handful of drivers that actually swing the outcome, and leaves everything else alone. For most early companies that's a short list: your growth rate, your churn (the share of customers who leave each month), your hiring pace, and one make-or-break event like a large deal closing.

Your base case is your honest expectation — not your hope, not your pitch deck. If you genuinely believe revenue grows 6% a month, that's the base. The upside flexes those same drivers in your favor: growth at 9%, churn a point lower, the big deal lands in Q3. The downside does the opposite: growth at 3%, churn creeps up, the deal slips to next year and you hired two people against revenue that didn't arrive.

• Growth rate — how fast new revenue comes in each month
• Churn — how much existing revenue you lose each month
• Hiring pace — how many people you add and when their cost starts
• The one big swing — a make-or-break deal, raise, or contract renewal

Decide your tripwires before you need them

The real power of three cases shows up when you attach triggers — specific, pre-agreed actions tied to a number you can watch. A tripwire turns "things feel scary" into "we said we'd do X when Y happened, so we're doing X." You make the hard call once, calmly, instead of arguing about it the week the bank balance gets thin.

Write them in plain if-then language. "If cash dips below four months of runway, we freeze all non-essential hiring." "If two months of actual revenue come in below the downside line, we cut planned marketing spend in half." "If we close the big deal by June, we green-light the two engineers we held back." The point is that the threshold and the response are both set in advance, so the decision is mechanical, not emotional.

What this looks like in dollars

Say you hold $600,000 in the bank and you're burning $50,000 a month — that's 12 months of runway, the time before cash runs out. In your base case, revenue grows enough to slowly shrink that burn, and 12 months stretches toward 15. Comfortable, not lazy.

In the upside, the big deal lands and burn drops to $30,000 a month; suddenly you have well over a year and a half, and the conversation becomes whether to invest faster. In the downside, growth stalls and you add two hires against flat revenue, pushing burn to $75,000 a month — that same $600,000 now lasts roughly 8 months. Seeing all three side by side is the point: the downside isn't a surprise anymore, it's a column with a plan attached.

Plans are living things

None of these three numbers will be exactly right, and that's fine — they're not predictions, they're a map of the territory you might travel. As real results arrive each month, you reforecast: you nudge the base case toward whichever scenario reality is tracking, and you check whether any tripwire just got closer. A plan you revisit monthly stays useful; one you build once and file away is just a prettier guess.

This month, take an hour and write your three cases on one page, flex only your real drivers, and set two or three tripwires with actual dollar thresholds. You'll trade a lot of future panic for a few minutes of present honesty.