Most business owners discover cash flow problems when the account is already low. A projection eliminates that surprise: it tells you in January that February will be a down month, and in March that April will bring a tax payment that cuts your net cash flow by $3,600. That information changes what you do in January and March — before the crunch arrives.
This post covers why cash flow differs from profit, the five rows every projection needs, a full worked example for a $240,000 service business, and the three gaps most projections miss.
Your P&L records revenue when you invoice. Your bank records it when the client pays. If you send a $10,000 invoice on March 28 with net-30 terms, your March P&L shows $10,000 in income. Your March bank statement shows zero — the cash arrives in late April.
Operating expenses run the other direction: some bills come due before the work is done (rent, payroll, software subscriptions), others arrive weeks after (subcontractors, materials). The gap between the P&L and the bank account can be thousands of dollars in any given month, and it compounds over time in ways that catch owners off guard.
The bottom line: Profit determines whether your business is worth running. Cash flow determines whether it can keep running this month. A business can be profitable and still run out of cash.
One month is too short — you cannot see seasonal dips or quarterly tax payments coming. One year is too uncertain to be actionable — revenue assumptions past month six are largely guesswork for most small businesses. Six months threads the needle: long enough to see structural problems (recurring low months, scheduled large expenses), short enough that your assumptions hold.
Review and roll the projection forward one month every four to six weeks. You are not trying to predict the future — you are tracking whether incoming data confirms or contradicts your earlier assumptions.
Every cash flow projection has the same structure regardless of business size.
Ann runs a two-person marketing agency. She bills $240,000 per year but revenue is uneven — January and May are strong, February is slower. Monthly operating expenses are $15,200. She pays $3,600 per quarter in estimated federal and state taxes using the prior-year safe harbor method.
| Expense Category | Monthly |
|---|---|
| Owner salary | $7,500 |
| Part-time assistant | $2,500 |
| Rent | $2,000 |
| Software & tools | $700 |
| Health insurance | $900 |
| Marketing | $500 |
| Phone, utilities, misc | $1,100 |
| Total Monthly Operating Expenses | $15,200 |
| Month | Cash In | Operating Exp. | Tax Payment | Net Cash | Ending Balance |
|---|---|---|---|---|---|
| January | $20,000 | $15,200 | — | +$4,800 | $16,800 |
| February | $14,000 | $15,200 | — | ($1,200) | $15,600 |
| March | $22,000 | $15,200 | — | +$6,800 | $22,400 |
| April 15 → | $20,000 | $15,200 | $3,600 | +$1,200 | $23,600 |
| May | $24,000 | $15,200 | — | +$8,800 | $32,400 |
| June 15 → | $20,000 | $15,200 | $3,600 | +$1,200 | $33,600 |
Two moments stand out. February shows negative cash flow (-$1,200) — the slow month does not cover fixed expenses. Ann enters that month with $16,800, so the dip brings her to $15,600, not zero. But if she had started the year with $5,000 instead of $12,000, February would leave her at $8,600 — just over two weeks of runway against a $15,200/month expense base. The projection makes that scenario visible in January, when she still has time to act.
April and June each carry a $3,600 tax payment that cuts the monthly net from $4,800 to $1,200. Without the projection, these payments arrive as surprises. With it, Ann allocates the April tax in March — when cash is flush at $22,400 — and the payment is a planned transfer, not an emergency.
The projection’s real value is not accuracy — it is advance notice. Ann will not collect exactly $14,000 in February. But she will be close. Even an approximation tells her the crunch is coming three to four weeks before it arrives. That window is the difference between a proactive response and a reactive one.
If you run net-30 or net-45 terms, the cash collected in any given month is not that month’s revenue — it is last month’s. Build your cash-in row from your receivables aging report, not from your current month’s invoice total. A $20,000 January in the worked example means $20,000 of December invoices were collected in January, not that $20,000 was billed and paid same-month.
Watch for slow-pay creep. If your average collection time stretches from 32 days to 47 days — a 15-day slip that is easy to miss — a $20,000/month revenue business loses roughly $10,000 in float. That shows up as a cash shortfall that has nothing to do with revenue or expenses. Track average days to collect as a separate metric alongside the projection.
Software renewals, insurance premiums, professional association dues, and business licenses often bill annually. If you average them out into a monthly figure for the projection, the month the bill actually arrives will show a cash shortfall even though you accounted for the cost. Put annual expenses in the specific month they are due, not spread across 12 months. The projection should match your actual bank statement, not a smoothed average.
If you are an S-corp or single-member LLC, distributions from the business to yourself are not operating expenses — they do not appear on your P&L. But they absolutely reduce your bank balance. Any month you draw beyond your payroll salary needs to appear in the projection as a cash outflow. Owners who omit this consistently project healthier cash positions than they actually have and are surprised when the account reads low despite a “profitable” P&L.
A negative month in the projection is not a crisis — it is a to-do item that arrived early. Four responses, in order of preference:
Small Business Dashboard Pro includes a dedicated 6-Month Cash Flow Projector tab — enter your monthly revenue and expense assumptions, and the running balance calculates automatically. Also includes monthly P&L, quarterly tax estimator, and all 19 IRS Schedule C categories. One-time purchase, no subscription.
Profit (net income) is revenue minus expenses on your income statement — it does not care when the money changes hands. Cash flow tracks the actual timing of money in and out of your bank account. A profitable business can be cash-flow negative in a given month if invoices are unpaid, a large expense lands, or a tax payment is due. The reverse is also possible: a business can show positive cash flow while losing money on paper if it collects advance payments before delivering. For day-to-day survival, cash flow is what matters. Both numbers are necessary for a complete picture.
The standard guidance is 3 to 6 months of operating expenses. For a business with $15,200 in monthly fixed costs, that is $45,600 to $91,200. The right number depends on revenue predictability: subscription or retainer businesses can operate with 2 to 3 months of reserve, while project-based or seasonal businesses should target 4 to 6 months. Build a 12-month projection, find the month with the lowest projected cash balance, and size your reserve to keep that minimum above zero under a moderate stress scenario — say, one client pays 30 days later than expected.
A cash flow statement is historical — it shows what actually happened to cash over a completed accounting period and is one of the three standard financial statements (alongside the income statement and balance sheet). A cash flow projection is forward-looking — it estimates what will happen to cash over future months based on expected revenue, expense timing, and one-time items. Projections are used for planning decisions (when to hire, when to draw on a credit line, when to invest). Statements are used for retrospective reporting and lender disclosure. You need both: the statement tells you what happened, the projection tells you what to do next.
A negative projected month is useful information, not a crisis — you are seeing it weeks in advance. Options include: accelerating collections with a small early-pay discount, deferring non-critical expenses until after the gap month, opening a business line of credit while you are still in a strong cash position (lenders approve on history, not projection), and front-loading business development to generate invoices that will collect before the low point. The worst response is to ignore the projection. Discovering a cash shortfall when the account is already empty eliminates every option except emergency borrowing at the worst terms.