Burn vs Runway: When to Cut Costs and When to Raise Money
Burn is how much cash you lose each month; runway is how many months that cash lasts. When runway shortens, a founder has three levers: cut costs, grow revenue faster, or raise funding. The right choice depends on what the next spend returns, how long a raise takes and how much runway you have left. A useful rule is to decide the date you must act by, and to act well before it.
Gross burn and net burn
- Gross burn: total cash going out each month
- Net burn: cash going out minus cash coming in
- Runway: cash on hand divided by net burn
Track net burn as a three-month average so one unusual month does not mislead you.
When cutting is the right first move
- Spend has not produced measurable return for 90 days
- Tools and vendors overlap, or contracts can be renegotiated
- Runway is under six months and a raise is not yet in motion
- Costs are growing faster than revenue
Cut what does not earn, and protect what drives revenue and retention.
When raising is the right first move
- Unit economics are proven and more spend would grow revenue profitably
- Runway is long enough to run a raise without negotiating from weakness
- You have the numbers an investor will ask for: cash forecast, KPIs and a clear use of funds
Do both when the numbers say so
Most startups pause weak spend and raise at the same time. Cutting first also improves the story: investors see discipline and a longer runway. Whatever you choose, write down the trigger date and who decides.
Put numbers on the decision
Use the runway calculator to test scenarios, the investor-ready financial model guide to prepare, and the Startup Burn Audit if you want every spend line reviewed. Book a free discovery call to talk it through.
Frequently asked questions
Burn rate is the cash you lose per month. Runway is how many months your cash lasts at that rate.
How much runway should I have before I start fundraising?Many founders aim to start with at least six months, because a raise often takes longer than expected. Your own timeline decides.
Should I cut costs before I raise?Often yes where spend has not produced measurable return, because it lengthens runway and shows discipline. Do not cut what drives revenue and retention.
How do I calculate net burn?Cash out minus cash in for the month, averaged over the last three months.
Want this set up for your startup?
Book a free discovery call. We review your numbers and agree what to fix first, with no cost and no obligation.
Written by Akram El-Karrar, CPA, from the work we do for startups every week.