How to Calculate Your Business Runway (and Extend It)
Quick answer: Business runway is how many months your business can survive at its current spending rate. The formula is simple: runway = cash on hand ÷ monthly burn rate. If you have ₹6,00,000 in the bank and spend ₹1,50,000 per month, your runway is 4 months. Knowing your number — and watching it weekly — is the most important single metric for any small business.
What is business runway?
Business runway is the length of time your business can operate before it runs out of money — assuming no new revenue comes in. It's a worst-case measure, and that's exactly why it's useful: it tells you how much time you have to fix a problem if things go wrong.
Every business has a runway, whether the owner knows it or not. The danger is not having a short runway — it's not knowing your runway and therefore not acting until it's too late.
The runway formula
Runway (months) = Cash on hand ÷ Monthly burn rateCash on hand = current balance across all business bank accounts and liquid funds (not receivables you're waiting to collect — only cash already in your account).
Monthly burn rate = total cash your business spends in a typical month (rent, salaries, stock, subscriptions, loan repayments, utilities — everything that goes out).
Worked example (in Indian rupees)
A small consultancy in Bengaluru has:
| Item | Amount |
|---|---|
| Bank account balance | ₹4,80,000 |
| Fixed costs per month (rent, salaries, software) | ₹1,20,000 |
| Variable costs per month (supplies, transport, marketing) | ₹40,000 |
| Total monthly burn | ₹1,60,000 |
Runway = ₹4,80,000 ÷ ₹1,60,000 = 3 months
This means the business can survive for 3 months even if it earns zero revenue. With some revenue coming in (but say 50% of normal due to a slow quarter), the effective runway extends — but you should plan against the worst case.
What this owner should do: with 3 months of runway, they are in a yellow zone — not an emergency, but not comfortable either. The target is 4–6 months. They need to either increase cash (collect receivables faster, close pending sales) or reduce monthly burn (pause non-essential costs) to get there.
Gross burn vs net burn: what's the difference?
Gross burn = everything going out each month (the number above).
Net burn = what goes out minus what comes in from revenue.
Net burn = Monthly costs − Monthly revenue collectedIf the same consultancy collects ₹80,000 in revenue in a month:
Net burn = ₹1,60,000 − ₹80,000 = ₹80,000/month
Runway on net burn = ₹4,80,000 ÷ ₹80,000 = 6 months
Use gross burn for worst-case planning (no revenue). Use net burn for realistic planning (current revenue continues). Both numbers matter; they tell you different things.
What is a healthy runway for a small business?
There is no universal answer, but practical benchmarks:
| Runway | Status |
|---|---|
| Under 2 months | Red — immediate action required |
| 2–3 months | Amber — start extending urgently |
| 3–6 months | Yellow — manageable, but keep watching |
| 6+ months | Green — comfortable buffer |
For a business with predictable, recurring revenue (subscriptions, retainer clients), 3 months may feel comfortable. For a business with lumpy, project-based revenue or high seasonality, 6 months is a more sensible floor.
6 ways to extend your business runway
1. Collect what you're already owed
Receivables are runway you've already earned but not yet collected. If customers owe you ₹3 lakh, chasing that aggressively is the fastest way to extend runway without cutting anything or selling more. Send reminders, make calls, offer a small early-payment incentive — and automate reminders so you stop leaving money on the table through forgetfulness.
2. Cut your burn rate by finding non-essential costs
Go through last month's bank statement and highlight every transaction above ₹500. For each one, ask: "Does this directly help the business this month?" Software you're not using, subscriptions that auto-renewed, services you pay for out of habit — these are common culprits. Even cutting ₹20,000/month extends a 3-month runway to 3.4 months; cut ₹40,000/month and it becomes almost 4 months.
3. Renegotiate supplier payment terms
If you're paying suppliers in 15 days, ask for 45. The cash stays in your account 30 extra days — which directly extends runway without reducing costs. Most reliable customers can negotiate this. Offer predictability (always paying on the agreed date) in exchange for longer terms.
4. Slow down discretionary spending
Not everything that's "planned" needs to happen now. Hiring, new equipment, marketing campaigns — all reasonable in good times, all negotiable when runway is tight. Deferring a ₹1 lakh expense by 60 days can mean the difference between 3 months and 3.75 months of runway.
5. Increase revenue with the least-resistance path
Look for the fastest path to more cash: a price increase for new work (existing commitments stay the same), upselling current customers, activating dormant leads, or offering a prepaid discount ("pay 3 months now at 10% off"). New customer acquisition takes time; monetising existing relationships is faster.
6. Get a working capital line before you need it
A business loan or overdraft facility taken when your runway is healthy is available at better terms and without panic. If you wait until runway is at 6 weeks, you're borrowing from a position of desperation — and lenders know it. Secure a line of credit when you have 4+ months of runway and keep it for genuine emergencies only.
Common mistakes when calculating runway
Including receivables as cash. Money customers owe you is not yet your money. Count only what's in your bank accounts.
Using average monthly costs instead of actual. Monthly costs vary — some months have annual renewals, quarterly payments, seasonal peaks. Use the last 3 months' average for a more accurate number, and separately flag any known large upcoming payments.
Not recalculating often enough. Runway changes every week. A business owner who calculated runway in January and checks again in March has missed 2 months of drift. Run the number monthly at minimum; weekly if runway is under 3 months.
Forgetting loan repayments. EMIs and loan repayments are cash going out — they belong in burn rate. Many owners forget to include them.
How Thola helps you track and extend your runway
Thola is built to keep these numbers visible without manual calculation. It reads 100+ signals from your business into a live health score (0–100) and flags when cash metrics move in the wrong direction — before the problem is serious.
Specific to runway:
- Cash position always visible — you don't need to open a spreadsheet to know where you stand.
- 12-month forecasts — see your cash position projected forward month by month, so you can spot a runway squeeze 2–3 months before it hits and act early.
- "Fix Now" warnings — when runway drops into the amber or red zone, Thola flags it and guides you to the next step.
- Receivables tracking — cash locked in overdue invoices is highlighted, because collecting it is the fastest runway extension most businesses have available.
Thola is a coach and a guardrail, not an autopilot — it shows you the number and guides you to the action, but you always make the call. Available in English, Tamil, Telugu, Kannada, Malayalam and Hindi.
6,000+ founders already run their business on Thola. Free to start; paid plans from ₹199/month.
Frequently asked questions
What is the formula for business runway? Runway (months) = Cash on hand ÷ Monthly burn rate. Cash on hand is the total in your bank accounts right now (not including receivables). Monthly burn rate is everything your business spends in a typical month. For example, ₹6 lakh in the bank with ₹1.5 lakh monthly costs gives you a 4-month runway.
What is a good business runway for a small business in India? A practical minimum is 3 months of gross burn (worst case, no revenue). Six months is comfortable for most small businesses. Under 2 months is a red-zone situation that requires immediate action — cutting costs, collecting receivables, or securing additional capital before the situation becomes a crisis.
What is the difference between burn rate and runway? Burn rate is how much cash your business spends each month. Runway is how long your current cash will last at that burn rate. They are two sides of the same calculation: reducing your burn rate (spending less) directly extends your runway without you needing to earn more.
Should I include receivables when calculating my business runway? No. Runway should only count cash already in your bank accounts. Receivables (money customers owe you) are not in your control — they could arrive late or not at all. Including them makes your runway look longer than it really is, which is dangerous. Calculate runway on confirmed cash; track receivables separately.
How often should I recalculate my business runway? At minimum, monthly — ideally weekly if your runway is under 4 months. Runway changes continuously as you spend and collect money. A business owner who only checks quarterly is flying blind for 3 months at a time. The more frequently you check, the more lead time you have to act if it starts dropping.