Operations · checklist
The 30-Minute Monthly Numbers Routine
A short, repeatable close that tells you whether last month actually made money — before your accountant does.
Most owner-run businesses find out how a month went three weeks after it ended, from someone else, in a format built for tax rather than for decisions. A half-hour routine on the first working day of each month closes that gap and costs nothing.
The five figures to write down
- Money in: everything that actually landed in the bank, not what you invoiced.
- Money out: total payments, split into fixed costs and variable costs.
- Closing bank balance, plus the total you still owe on cards and finance.
- Unpaid invoices, grouped by how overdue they are: current, 30 days, 60 days, older.
- Hours or jobs delivered, so revenue can be read per unit of work rather than in the abstract.
Keep them in one spreadsheet with one row per month. Twelve rows is enough to see a trend, and a trend is what tells you whether a bad month was weather or direction.
The three questions the figures answer
| Question | Calculation | Warning sign |
|---|---|---|
| Did the month pay for itself? | Money in − money out | Negative twice in a row with no known cause |
| How long could I survive on nothing? | Bank balance ÷ average monthly fixed costs | Under two months |
| Is my invoicing slipping? | Overdue invoices ÷ monthly revenue | Above roughly a third |
Profit and cash are different problems
A profitable month can still empty the bank if customers pay late and suppliers do not wait. Track both figures; fixing the second is usually faster than fixing the first.
What to do with a bad month
Resist cutting the costs that generate work. In order, chase overdue invoices, pause discretionary subscriptions, then reprice the least profitable line of work. Cutting marketing first is the change that feels safest and hurts longest.
Run the figures through the cash flow and net profit calculators on this site if you would rather not build the spreadsheet yourself — both take the same five inputs.
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