How long does the money actually last?

Because runway is a cash question. Revenue is recognised when it is earned, and cash arrives when someone actually pays. A business with strong invoiced revenue and slow collections can run out of money while its accounts look healthy, which is one of the commonest ways founders overstate how long they have.

GST, TDS, provident fund and deferred salaries sit in the bank balance looking like runway right up until the day they leave. Dividing the full balance by monthly burn counts that money twice. Holding it back gives you the figure you can actually spend.

The common guidance is to start fundraising at around nine to twelve months of runway, because raising in India frequently takes longer than founders plan for and negotiating from a short runway weakens your position. What matters more than the number is whether you would still have choices if the next quarter went badly.

It is a straight-line estimate and should be treated as one. It assumes costs hold steady, nothing one-off lands, and collections behave as you described. Real runway moves with the timing of receivables and lumpy payments, which is exactly the work a proper cash forecast does.