The Cash Math Every Bootstrapped Founder Should Run Every Month
Without investors, cash timing is the business. The numbers to track, the money that only looks like yours and the levers that buy months of runway.
A bootstrapped company can be profitable on paper and still run out of money. Revenue is recorded when you earn it. Rent, payroll and suppliers are paid in cash, on their schedule, and nobody is standing by with a bridge round when the two fall out of step.
That is why self-funded founders who last tend to manage cash with a discipline that venture-backed peers can postpone for a while. The core routine is not complicated, but it has to happen monthly, from bank data, not from a forecast you wrote in a good week.
Many operators also keep a rolling 13-week cash forecast: a simple week-by-week table of expected receipts and payments. It is short enough to be accurate and long enough to see a payroll squeeze or a large annual bill coming before it arrives.
The three numbers to know cold
The first is net burn: cash out minus cash in for the month, taken from bank statements rather than the profit and loss report. The second is runway: cash on hand divided by average net burn over the last few months. The third is gross margin, the share of each sale left after the direct cost of delivering it.
Gross margin is the one founders underweight. Growth on a thin margin consumes cash, because each new customer requires money to serve before their payment arrives. A business with healthy margins can often fund its own growth. One without them grows itself into a cash crisis.
Money that only looks like yours
Some cash in your account belongs to someone else. Sales tax collected from customers is held for the state. Payroll taxes withheld from employees’ wages are held for the government, and the IRS treats unpaid withholding very seriously, including the possibility of personal liability for the people responsible for paying it.
Customer prepayments are real cash, but they come with an obligation to deliver. If a large share of your balance is annual subscriptions paid in advance, the work to earn that money is still ahead of you. Track these balances separately so a healthy-looking account does not encourage spending you cannot support.
The levers that buy you runway
Payment terms are the quietest lever. Getting paid in advance, at signing or on shorter terms improves cash without a single new sale. Offering a modest discount for annual prepayment can be worth it when cash is tight, as long as the margin can absorb it.
Collections are the next lever. Send invoices the day work is delivered, follow up on a fixed schedule and make paying you easy. Many small businesses lose more cash to slow invoicing than to slow sales.
On the cost side, distinguish between commitments you can cancel in a month and those you cannot. Annual software contracts, long leases and fixed hires are the expenses that turn a slow quarter into a dangerous one. Prefer flexibility until revenue is predictable.
Price is the lever founders reach for last and should consider first. A modest price increase on new customers improves margin on every future sale without adding any cost. Test it on new deals before applying it to existing customers, and watch whether win rates actually change.
Borrowing without betting the house
Debt can smooth timing gaps, and lenders backed by government guarantee programs exist for small businesses that cannot get conventional terms. Read any personal guarantee carefully. Many small business loans require one, and it means the founder is on the hook personally if the company cannot pay.
Credit cards and merchant cash advances are fast but often expensive, and the cost is not always expressed in a way that is easy to compare. Calculate the effective annual cost before agreeing to anything presented as a simple fee.
The best time to arrange a credit line is when you do not need it. Lenders look at recent results, and a business applying in the middle of a cash squeeze is asking at the worst moment. If a line is available on reasonable terms while things are going well, setting it up as a backstop can be cheap insurance.
The monthly routine
On the same day each month, pull bank balances and the last month’s transactions. Calculate net burn and runway, and subtract any money you are holding for taxes or customers before you call the rest available.
List receivables by age and chase anything overdue. List upcoming fixed commitments for the next quarter. Then decide, in writing, what you will do if runway drops below a threshold you set in advance.
Writing the trigger down matters more than the exact figure. Founders who decide in advance when they will cut costs or raise prices act early. Founders who wait for certainty usually act once the options have already narrowed.
This is general information, not financial advice. Nothing here is a recommendation to buy or sell anything; speak to a licensed adviser about your own position.
