05ExplainerFoundational
Why profitable businesses still run out of cash
Profit tells you whether your business makes money over time. Cash tells you whether you can pay the bills this week. Here's why the two drift apart, with a month-by-month example.
By Khalel Dumaz, Founder of Vora IQ
Published
The short answer
Profit is what's left after you subtract expenses from the revenue you've earned in a period. Cash flow is the money that actually moves in and out of your bank account. The two drift apart when customers pay late, when you pay for inventory or equipment upfront, or when you grow quickly, so a profitable business can still be unable to pay its bills.
- Level
- Foundational
- Reading time
- 7 minutes
- Updated
- Sources
- 1 cited
- Useful for
- All business types
Understand
The direct answer, in plain language, and why it matters.
Profit and cash measure different things
Profit answers one question: over this period, did you earn more than it cost to earn it? Cash answers another: how much money is in the bank right now, and will there be enough when the bills are due?
The difference comes from timing. The U.S. Small Business Administration explains that the accrual method of accounting puts a transaction on the books as soon as the sale is completed, while the cash method records it only once payment has been received.[1] So under accrual accounting, your profit can include money a customer still owes you. The SBA lists "potentially deceiving figures" among the drawbacks of the accrual method, and "shows cash flow clearly" among the advantages of the cash method.[1]
Why it matters
You pay staff, suppliers, rent, and taxes with cash, not with profit. A business that runs out of cash can't keep operating long enough to collect the profit it has already earned.
Growth, which feels like the cure for every problem, can make the gap worse. More sales usually means more inventory to buy, more people to pay, and more invoices waiting to be collected, all before the new revenue arrives.
Apply
The framework, a worked example, and the steps to take.
Where the gap comes from
| Cause | What happens to profit | What happens to cash |
|---|---|---|
| Customers pay on credit terms | Counted when you complete the sale | Arrives weeks or months later |
| Inventory bought ahead of sales | Counted as a cost only when the items sell | Leaves when you pay the supplier |
| Equipment purchases | Spread across the equipment's useful life | Leaves all at once, or as loan payments |
| Loan repayments | Only the interest counts as an expense | The full payment leaves every month |
| Owner draws | Don't reduce profit | Leave when you take them |
| Income taxes | Calculated on profit for the period | Paid on the tax authority's schedule, sometimes in large amounts |
| Seasonality | Busy months look great | Cash from busy months has to cover the slow ones |
Worked example
Hypothetical scenarioA cleaning company wins a big contract
A small commercial cleaning company in Raleigh brings in $20,000 a month from existing clients, who pay by card at the end of each month. Its costs are $17,000 a month, paid as they come up. It has $18,000 in the bank.
At the start of month 2, it signs a contract to clean an office park for $24,000 a month. The client pays invoices 60 days after they're issued. Serving the contract adds $18,000 a month in wages and supplies, paid every two weeks, plus a one-time $4,000 for hiring and training in month 2. The company invoices at the end of each month.
| Month | Revenue earned | Costs | Profit | Cash in | Cash out | Cash at month end |
|---|---|---|---|---|---|---|
| 1 | $20,000 | $17,000 | $3,000 | $20,000 | $17,000 | $21,000 |
| 2 | $44,000 | $39,000 | $5,000 | $20,000 | $39,000 | $2,000 |
| 3 | $44,000 | $35,000 | $9,000 | $20,000 | $35,000 | −$13,000 |
| 4 | $44,000 | $35,000 | $9,000 | $44,000 | $35,000 | −$4,000 |
| 5 | $44,000 | $35,000 | $9,000 | $44,000 | $35,000 | $5,000 |
Over five months the company earns $35,000 in profit. It's profitable every single month. Yet by the end of month 3 it's $13,000 short, with payroll due. To keep going, it has to borrow, delay paying suppliers, or put costs on a personal credit card.
The money hasn't disappeared. At the end of month 3, the office park owes the company $48,000 for two months of work. The cash is sitting in the client's account, not the company's.
Now change one term. If the company negotiates 30-day payment instead of 60, the month 2 invoice is paid in month 3. Cash at the end of month 3 becomes $11,000 instead of −$13,000, and the lowest point is the $2,000 at the end of month 2. That's tight, but it's positive.
How to see the gap before it hits you
- 01
Forecast cash week by week
Build a simple spreadsheet with one column per week for the next 13 weeks, about one quarter ahead. Weekly matters because payroll and rent don't wait for the end of the month.
- 02
Record cash in on the date you'll actually be paid
Use the date the money is likely to arrive, not the invoice date. If a client's terms say 30 days but they usually pay in 45, use 45.
- 03
List every cash outflow
Include the ones profit hides: loan principal, owner draws, tax payments, annual insurance premiums, inventory orders, and equipment.
- 04
Find the lowest point
Look for the week where your balance is lowest. That number, not your profit, tells you how much room you have.
- 05
Decide what you'll do before you get there
Options include asking for a deposit, invoicing more often, shortening payment terms, arranging a line of credit before you need it, ordering inventory in smaller batches, or phasing in new hires.
- 06
Update it every week
Replace forecasts with actual numbers as each week closes. The forecast gets more accurate, and you'll see problems weeks earlier.
Where the gap shows up by business type
How this differs by business type
You pay staff every week or two, but commercial clients may pay monthly or later. Seasonal businesses, like landscaping or snow removal, need busy months to fund slow ones.
Inventory is the big one. You may pay a manufacturer months before the stock sells, and minimum order sizes can tie up more cash than a month of sales brings in.
Payment terms and client concentration. When one large client pays late, it can leave a hole in your payroll. Ask for a deposit or monthly billing on longer projects.
Acquisition cost is spent upfront and earned back over months, as unit economics shows. Annual prepaid plans can help, because the cash arrives before you deliver the service.
Many venture-backed companies deliberately spend more than they earn while they grow, so the key number is runway: months of cash left at the current burn rate. Plan to raise money well before it runs out.
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Advance
Your next action, the right tool, and where to go next.
What to do next
Build your 13-week cash forecast this week, starting with the payment dates of every open invoice and every bill due. If customer acquisition is a big upfront cost for you, read unit economics and run your numbers through the unit economics calculator to see how long each customer takes to pay back. If you're setting prices and payment terms for a new offer, read pricing your first product and decide upfront whether to ask for a deposit.
Help me build a 13-week cash flow forecast for my business, [describe your business]. My current bank balance is [amount]. Here are my expected cash inflows, with the date I expect each payment to actually arrive: [list]. Here are my expected cash outflows, with due dates, including payroll, rent, loan payments, owner draws, taxes, and inventory: [list].
Lay this out as a table with one column per week. Show total cash in, total cash out, and the ending balance for each week. Highlight the week with the lowest balance. Then suggest three specific actions I could take to raise that low point, and show the effect of each on the forecast. Don't add any income or costs I haven't listed; ask me if something seems missing.
Key takeaways
- Profit measures what you've earned over a period. Cash is what you can spend today.
- Late-paying customers, upfront inventory or equipment, loan repayments, and fast growth all pull the two apart.
- A business can be profitable every month and still run out of cash.
- A weekly cash forecast shows you the lowest point in advance, while you still have options.
Questions founders also ask
Frequently asked questions
What's the difference between accrual and cash accounting?
Under the accrual method, a sale goes on the books as soon as it's completed, even if the customer hasn't paid yet. Under the cash method, it's recorded only once the payment arrives. That's why accrual profit can include money customers still owe you. The U.S. Small Business Administration lists potentially deceiving figures as a drawback of accrual accounting, and clear cash flow as an advantage of the cash method. An accountant can advise which method fits your business.
How do you build a 13-week cash flow forecast?
A 13-week cash flow forecast is a spreadsheet with one column per week for the next quarter. Enter each expected payment on the date it's likely to arrive, not the invoice date, and list every outflow, including loan principal, owner draws, taxes, insurance, and inventory. Find the week with the lowest balance and decide in advance what you'll do about it. Replace forecasts with actual numbers as each week closes.
What can you do if your business is profitable but short on cash?
When a profitable business is short on cash, find the lowest point in your cash forecast and act before you reach it. Options include asking for deposits, invoicing more often, shortening payment terms, ordering inventory in smaller batches, and phasing in new hires. Arrange a line of credit before you need it, not when the account is nearly empty. A bookkeeper or accountant can help you track profit and cash separately.
Does an unpaid invoice count as cash?
No. Under accrual accounting, an unpaid invoice can count toward profit, but it isn't cash until the money reaches your bank account. Customers can pay late, pay less, or not pay at all, and you can't cover payroll or rent with money a client still owes you. In a cash forecast, record each invoice on the date you realistically expect to be paid, which may be later than its terms say.
Can growing too fast cause cash flow problems?
Yes. Fast growth can widen the gap between profit and cash, because more sales usually means buying more inventory, paying more people, and waiting on more invoices, all before the new revenue arrives. In a hypothetical example, a cleaning company that wins a contract paying 60 days after each invoice is profitable every month yet ends its third month $13,000 short. Forecast your cash week by week before taking on a large new customer.
Sources
Every externally sourced claim links back here. We explain ideas in our own words and link to the original work. See the full source index.
- [1]Manage your business: manage your finances
U.S. Small Business Administration
Official guidance · Accessed November 3, 2026
Khalel Dumaz is the founder of Vora IQ, which publishes The Founder Almanac, and the author of The Vibe Code Bible, a free guide to building software with AI.
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