Small Business Cash Flow: The Weekly Numbers That Matter
Profit is an accounting result; cash is what pays next week’s bills. A one-page weekly cash view prevents most small-business surprises.
A profitable business can still run out of money. Profit is recorded when work is delivered; cash arrives when a customer pays, sometimes weeks later. If payroll, suppliers, and tax fall before that payment, the bank balance decides what happens, not the profit figure. Cash flow management is the discipline of seeing that gap before it becomes a crisis.
Build a one-page weekly view
At the start of each week, list the money you expect to receive and the money you must pay, by date. Include confirmed invoices, recurring subscriptions, supplier terms, loan payments, wages, and tax deadlines. Do not include hoped-for sales until they are confirmed.
The result is a running balance: opening cash, money in, money out, closing cash. If the closing figure goes negative in any week, you have found the problem while there is still time to act.
Know the three numbers
- Cash runway: how many weeks the current balance can cover committed costs.
- Collection period: the average days between invoicing and payment.
- Gross margin: what remains from each sale after direct costs.
Together they explain most cash problems. Slow collections and thin margins produce a shortfall even when sales look healthy. A long runway gives you room to fix either one without borrowing at short notice. Check them monthly as well as weekly: the weekly view catches timing problems, while the monthly trend shows whether the business is slowly improving or slowly tightening.
Separate operating cash from reserves
Keep a tax reserve and a buffer in separate accounts. Tax money is not available to spend, even if it sits in the business account. Move it when each payment arrives, not at the end of the year.
A buffer of four to eight weeks of committed costs is a reasonable target for a small service business. It is not a substitute for profit; it is the space to make decisions without panic.
Shorten the gap between work and payment
Invoice immediately after delivery, state the due date clearly, and follow up on the first day a payment is late. Offer a small discount for early payment only if your margin can absorb it. For larger projects, charge a deposit before work begins and progress payments at agreed milestones.
Where possible, negotiate supplier terms that match your collection cycle. Paying suppliers in fourteen days while customers pay in forty-five creates a permanent hole that growth makes larger.
Review weekly, not monthly
Ten minutes every Monday is enough. Update the actual balance, add new commitments, and check the next four weeks. A monthly review is too late for a payroll decision; a weekly habit catches the problem while options remain. Put the review in the calendar and keep it short; consistency matters more than detail.
If you are still building the first sales that feed this system, start with our guide to earning your first 1,000 dollars from a side business. The SBA's guide to managing business finances covers forecasting and recordkeeping in more detail.
Frequently Asked Questions
What is the difference between cash flow and profit?
Profit is revenue minus expenses over a period, regardless of when cash moves. Cash flow tracks when money actually enters and leaves the bank. A business can be profitable and still run out of cash.
How much cash reserve should a small business keep?
Four to eight weeks of committed costs is a common starting point for service businesses. Product or seasonal businesses may need more, especially around inventory purchases.
Should I pay myself a salary?
Yes, once the business can support it. A fixed owner payment makes the true cost of the business visible and prevents personal spending from quietly draining operating cash.
How do I handle late-paying customers?
Invoice promptly, state terms in writing, and follow up on the due date. For repeat late payers, require a deposit or pause work until the account is current.