HOTCB Insights, SBAMarch 2026Business

How Long Until You Run Out of Cash?

29% of startups fail from running out of cash. Know your runway and when to raise. Model pessimistic, realistic, and optimistic scenarios.

Ready to run the numbers?

Calculate Your RunwayUse the calculator below to see how this story affects you personally

๐Ÿ“‹ Quick Examples โ€” Click to Load

Your Numbers

Rent, salaries, insurance
Materials, marketing
%
Runway
4.0 months
Burn rate: $25,000/mo
Funding for 12mo: $200,000
Break-Even Month
36
Pessimistic Runway
3 mo
Realistic Runway
4 mo
Optimistic Runway
5 mo

Charts

Cash Balance Over 24 Months (3 Scenarios)

Monthly Revenue vs Costs

Cost Breakdown

Runway by Scenario

For educational and informational purposes only. Verify with a qualified professional.

Cash runway is how many months your business can operate before running out of cash. Burn rate = monthly costs minus monthly revenue. Startups typically aim for 12-18 months of runway. Plan fundraising when you have 6-12 months left. Revenue growth extends runway; cost cuts do too. Model pessimistic, realistic, and optimistic scenarios to see your range.

12-18
Target runway (mo)
6-12
Start raise when
3-6
Mo to close round
Burn
Costs - revenue

Sources: SBA, startup benchmarks.

Key Takeaways

  • โ€ข Runway = cash รท burn rate. Burn = fixed + variable costs - revenue.
  • โ€ข Start fundraising when you have 6-12 months left. Closing takes 3-6 months.
  • โ€ข Revenue growth extends runway. Model -20%, realistic, and +20% scenarios.
  • โ€ข One-time expenses (equipment, legal) deplete cash immediately. Plan for them.

Did You Know?

๐Ÿ”ข 29% of startups fail due to running out of cash (CB Insights)
๐Ÿ“Š Average Series A raise extends runway by 18-24 months
๐Ÿ’ก Reducing burn by 20% can extend runway by 25%
๐ŸŒ Seasonal businesses need larger cash buffers for slow months
๐Ÿ“ˆ 10% monthly revenue growth can double runway in a year
๐ŸŽฏ Break-even month = when revenue exceeds costs (with growth)

How Does Runway Work?

Burn Rate

Monthly burn = fixed costs (rent, salaries, insurance) + variable costs (materials, marketing) - revenue. Negative burn means cash flow positive.

Runway

Runway = (cash - one-time expenses) รท burn rate. If burn is zero or negative, runway is effectively infinite.

Scenarios

Pessimistic: revenue -20%. Realistic: current revenue. Optimistic: revenue +20%. Growth rate compounds each month.

Expert Tips

Cut costs before raising. Investors prefer lean teams. Every dollar saved extends runway.
Model revenue growth conservatively. Plan for 50% of what you hope. Under-promise, over-deliver.
Build a 12-month runway buffer. If you need $500K for 12 months, raise $750K for cushion.
Track runway weekly. Update revenue and cost projections. Runway can change fast.

Runway Benchmarks

StageTypical RunwayAction
Pre-seed12-18 moBootstrap or angel
Seed18-24 moProduct-market fit
Series A18-24 moScale
ProfitableInfiniteReinvest or grow

Frequently Asked Questions

What is cash runway?

Cash runway is the number of months your business can operate before running out of cash at the current burn rate. Runway = cash balance รท monthly burn rate. Burn rate = monthly costs minus monthly revenue. Typical startups aim for 12-18 months.

How do I calculate burn rate?

Monthly burn rate = monthly fixed costs + monthly variable costs - monthly revenue. Fixed costs include rent, salaries, insurance. Variable costs include materials, marketing. If revenue exceeds costs, you have positive cash flow and runway extends.

When should I raise funding?

Start fundraising when you have 6-12 months of runway left. Investors typically need 3-6 months to close. Running out of runway during a raise weakens your negotiating position. Plan ahead.

What is a good runway for a startup?

12-18 months is common for early-stage startups. Pre-revenue companies often aim for 18-24 months. SaaS businesses with recurring revenue can operate on 6-12 months of runway.

How does revenue growth affect runway?

Positive revenue growth extends runway by reducing net burn over time. A 10% monthly growth rate can dramatically extend runway. The calculator models pessimistic (-20%), realistic, and optimistic (+20%) scenarios.

What if I have seasonal revenue?

Seasonal adjustments smooth revenue across months. Use a seasonal factor (e.g., 0.8 in slow months, 1.2 in peak months) to model uneven cash flow. Adjust monthly revenue to reflect typical seasonality.

Key Statistics

29%
Fail from cash (CB Insights)
12-18
Target runway (mo)
3-6
Mo to close round
20%
Cost cut = 25% more runway

Official Data Sources

โš ๏ธ Disclaimer: This calculator is for educational purposes only. Runway and burn rate estimates are illustrative. Actual results depend on revenue accuracy, cost control, and market conditions. Consult a financial advisor or CFO for business planning. Not financial advice.

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