Runway is the number of months a business can continue operating at its current burn rate before exhausting its cash reserves: Runway = Cash Balance / Monthly Net Burn Rate. It is a survival metric used by startups, venture-backed companies, and early-stage businesses to plan fundraising timing and operational decisions. The SBA's small business financial management resources and FDIC's economic research both reference cash adequacy as a top small-business risk factor. See sba.gov and fdic.gov/bank/analytical/cfr for related guidance.
Runway answers the existential question: 'How long can we survive without new revenue or new capital?' It is calculated by dividing the current cash balance by the monthly net cash outflow (burn rate). A company with $1.2M in cash burning $100K/month has 12 months of runway. Gross burn vs. net burn distinction: - Gross burn rate: total monthly cash outflow (all operating expenses) - Net burn rate: gross burn minus cash received from revenue/customers - Runway typically uses net burn — gross burn-based runway overstates urgency if the business has meaningful revenue Runway benchmarks: Most venture investors and advisors recommend maintaining 18-24 months of runway. This buffer allows time to raise the next round, pivot, or build toward profitability. With 12 months, a fundraise should be actively underway. Below 6 months is typically distress — lenders and investors both treat sub-6-month runway as a material risk. Operational implications: Runway drives tactical decisions: When does payroll stretch? When do vendor payment terms need renegotiation? When must a growth-stage business begin bridge financing conversations? For lenders evaluating startups and early-stage businesses, runway is a proxy for the probability of repayment before the business runs out of capital. An 18-month runway with a credible path to break-even is a fundable position; a 3-month runway without a clear capital raise in progress is not. Extending runway: Runway can be extended by reducing gross burn (cost cuts), increasing revenue (accelerating collections, closing deals), or injecting capital (equity raise, venture debt, revenue-based financing). Many lenders offer 'runway extension' credit products specifically designed to provide capital before a business faces cash crisis. See sba.gov for SBA working capital programs.
Investors check runway to assess urgency and negotiating leverage. A company with 6 months of runway is in a weak negotiating position — it needs capital quickly. A company with 24 months of runway can be selective. Investors also assess whether the team has a credible plan to reach the next milestone before runway exhausts. Runway relative to plan — not absolute months — is the key signal.
For early-stage or cash-flow-negative businesses, lenders assess runway as a repayment risk factor. A business with less than 6 months of runway and no clear revenue inflection point is typically unbankable through conventional debt. Revenue-based financing, venture debt, or bridge capital from equity investors are more realistic options. Strengthening runway (via cost cuts or equity injection) before applying improves underwriting outcomes.
For growth-stage businesses: 18-24 months provides adequate buffer for fundraising cycles. For profitable small businesses (burn rate near zero), runway is less critical — days-cash-on-hand (typical for stable businesses) is the relevant metric. For businesses in volatile industries or those expecting cyclical cash flow dips, maintaining 3-6 months of gross operating expenses in liquid reserves provides meaningful protection against disruption.