Scenario planning is building three versions of your operating plan and deciding in advance what would make you switch between them. For a venture-backed startup the three cases are base, downside, and default-alive, and each one needs a runway number and a written trigger attached.
The cases are the easy part. Almost every founder can produce a spreadsheet with revenue 30% lower. The part that gets skipped, and the part that actually protects the company, is writing down the specific conditions that move you from one case to the next, before anyone is under pressure.
Why this matters more for 2027
Capital is concentrated rather than scarce. Global venture investment hit a record in the first half of 2026, but deal count stayed well below the 2021 peak, and the overwhelming majority of dollars went to artificial intelligence companies. The median gap between seed and Series A has stretched past 600 days.
Translated into planning terms: assume your next round takes longer and demands more proof than your last one did. A plan with one case and 18 months of runway is a bet that the market cooperates on your schedule. Our guide to building your 2027 annual operating plan covers the funding data in more detail.
The three cases
Base case
What you actually expect, and what the board approves as the operating plan. Revenue built from pipeline and cohort behavior, the full hiring plan, normal program spend.
The base case should be achievable, not aspirational. If your base case requires everything to go right, you have built a best case and mislabeled it, and every downstream decision inherits that error.
Downside case
Revenue lands meaningfully below plan while the market stays open. This is the most likely thing to go wrong, and it is the case most founders build carelessly.
A useful downside is not the base case with a haircut applied to the total. It is specific about what fails: the enterprise deals slip a quarter, the new segment does not convert, two large customers churn, the pricing change does not hold. Then hiring and program spend adjust in response.
Most companies model revenue at 60% to 70% of base here. The number matters less than the specificity.
Default-alive case
The case where you reach profitability, or at least cash-flow neutrality, on the cash you already have and never raise again.
Most Series A companies cannot reach this without cuts that would change what the company is, and that is fine. The point of building it is not to plan for it. The point is to know exactly what it would require: which hires never happen, which programs stop, what the team looks like, and what revenue level makes the math work. Founders who have done this arithmetic negotiate their next round from a materially different position than founders who have not.
What actually changes between cases
Four things move. Nothing else should.
Revenue. New bookings, expansion, and churn each flex separately. A single blended growth rate does not survive scrutiny.
Hiring. The biggest lever you control, because payroll is 60% to 75% of spend. In a downside case, hires get deferred rather than cancelled, which is why hiring triggers matter so much.
Discretionary program spend. Paid marketing, events, travel, contractors, conferences. Know in advance which of these you can cut inside 30 days without breaking anything, and which take a quarter to unwind.
Timing of committed costs. Renewals, leases, and annual contracts do not flex on demand. Map when each one comes up for renewal, because that is when you actually get the option to change it.
What should not change between cases: your gross margin assumptions, your cost structure percentages, and your collection timing, unless you have a specific reason. Flexing every variable at once produces three spreadsheets nobody believes.
Runway in each case
Runway is cash divided by net monthly burn, and the useful version of that calculation is more specific than it sounds. Our guide to burn rate and runway covers the four ways the standard formula misleads, including the difference between trailing and forward burn.
For scenario work, what matters is this: calculate runway on forward projected burn in each case, not on your trailing three-month average. Trailing burn tells you about a company that no longer exists once the plan changes.
Then produce one line per case:
- Base: X months, cash-out month, and the date you would need to start raising
- Downside: Y months, and the same two dates
- Default-alive: the month you reach cash-flow neutral, or the statement that you cannot get there
The gap between base and downside runway is the number to internalize. If base gives you 24 months and downside gives you 14, that 10-month spread is your actual planning risk, and it should drive how early you set triggers.
Triggers: the part everyone skips
A scenario without a trigger is an exercise. The trigger is what makes it a plan.
A good trigger has three properties. It is measurable, so there is no debate about whether it fired. It is early, so you still have options when it does. And it names the action, so nobody has to decide under pressure.
Weak: “If revenue underperforms, we will reduce spend.”
Strong: “If Q1 bookings land below $400,000, we defer the two Q2 engineering hires and cut paid marketing by half, effective April 1.”
Set triggers on leading indicators rather than lagging ones. Pipeline coverage tells you about Q2 in January. Revenue tells you about Q1 in April, when it is too late to do much about it.
Three or four triggers is the right number. A list of twelve does not get monitored.
Review them at the same monthly meeting where you review budget versus actual. The variance review is where you find out whether a trigger fired, so they belong on the same agenda.
When the downside case becomes a financing decision
Bridge rounds have become common again, for the reasons in the funding data above: rounds take longer, and companies that planned on 18 months find themselves needing 6 more.
The planning discipline is straightforward. Decide in advance the runway level at which you start a bridge conversation, and make it earlier than feels necessary. Raising a bridge with 9 months of runway is a negotiation. Raising one with 4 is an acceptance of whatever terms are offered.
Your existing investors are the first call, and they will ask two questions immediately: what changed against the plan, and what does the money buy. Having a downside case you built in October, rather than one you assembled the week before the call, is the difference between a company managing a plan and a company reacting to a surprise.
Presenting scenarios to a board
Three rules.
Lead with the base case. It is the plan. The other two are context for it, not alternatives competing for approval.
Show the runway spread explicitly. Base versus downside, in months, on one slide. That single comparison communicates more than the full model.
Bring the triggers, not just the cases. A board that sees measurable triggers with named actions concludes that you are managing the risk. A board that sees three spreadsheets and no triggers concludes you produced three spreadsheets.
Our guide to what goes in a startup board reporting package covers where this sits in the standing format.
Four ways scenario planning goes wrong
The downside is not really down. Revenue trimmed 10% while every hire stays in the plan is not a downside case. If nothing about the operating plan changes, you have not modeled anything.
All three cases are built at once and never revisited. Scenarios are only useful if they get compared to reality. Check quarterly whether you are tracking base or drifting toward downside.
The cases flex costs automatically. A model where expenses scale down neatly with revenue is describing a company that does not exist. Payroll is committed until someone makes a decision. Model the decision, not an automatic adjustment.
The scenarios live only in finance. If the VP of Engineering does not know which two hires are deferred in a downside case, the case does not function when it is needed.
Download the model
The 2027 budget model we use with clients is free to download, no email required. Linked P&L, balance sheet, and cash flow, with monthly burn and runway at the bottom.
To build a downside case, save a second copy and change three things: cut the new ARR line, push the start month on any hire you would defer, and reduce discretionary spend on the OpEx tab. The runway row at the bottom of the Cash Flow tab does the rest.
Common questions
How many scenarios should a startup build?
Three. Base, downside, and default-alive. Companies that build five or six rarely maintain any of them, and the extra cases usually differ by amounts too small to drive different decisions.
What is a default-alive scenario?
The case where the company reaches cash-flow neutrality on existing cash without raising again. Most early-stage companies cannot get there without changing what they are, but knowing precisely what it would take is valuable on its own, particularly heading into a fundraise.
How much should revenue drop in a downside case?
Most companies model 60% to 70% of base. What matters more than the percentage is naming the specific thing that fails, because that is what tells you which costs you can actually adjust in response.
How often should scenarios be updated?
Refresh them quarterly, and revisit them immediately after anything that changes the picture materially: a large customer loss, a missed quarter, a pricing change, or a shift in the funding market.
Do investors ask for scenarios?
Frequently, at Series A and above, and always in diligence. Our Series A due diligence checklist covers what investors test in the model itself.
What is the difference between scenario planning and a forecast?
A forecast is your single best estimate of what happens. Scenario planning is a set of cases with decisions attached to each. The forecast tells you where you are heading. The scenarios tell you what you will do if you are wrong.
Want a second set of eyes on your downside case before it goes to your board? Start a conversation.