"Profitable but cash-poor" is one of the more uncomfortable phrases in small business. A business with healthy P&L margins can still run out of cash if customers pay slowly, suppliers want quick payment, and inventory or work-in-progress ties up working capital. The way out is active cash flow management — forecasting, KPIs, credit control — rather than hoping it works out. This guide covers the major disciplines.
Each section links to a detailed companion piece for the specific practical area.
Cash flow problems compound
A late-paying customer triggers a missed supplier payment, which damages the supplier relationship, which results in tighter terms going forward, which constrains future activity. The cycle starts small and accelerates. Active management catches the first late payment; passive management catches the third missed supplier.
The 12-month rolling cash flow forecast
A useful cash flow forecast covers 12 months ahead and is updated monthly. The structure:
- 1Opening cash balance (today's actual).
- 2Forecast inflows by month: customer receipts, VAT refunds, capital injections, asset sales.
- 3Forecast outflows by month: supplier payments, payroll, rent, utilities, tax, VAT, loan repayments, capital expenditure.
- 4Closing cash balance per month.
- 5Lowest balance through the forecast period (the "trough") — what triggers concern.
For small businesses, a spreadsheet is sufficient. For more complex businesses, dedicated tools (Float, Fluidly, FUTRLI) integrate with the accounting software and refresh forecasts automatically.
Common causes of cash flow problems
- Slow customer payment (debtor days too high).
- Fast supplier payment requirements (creditor days too low) without negotiation.
- Inventory tied up too long.
- Work-in-progress on long projects with infrequent invoicing.
- Excessive owner drawings versus profitability.
- VAT lumpiness (collect monthly, pay quarterly) with mistimed cash retention.
- Tax liability undersaving (corporation tax due 9 months and 1 day after period end; shock if not provisioned).
- Capital expenditure timing without facility planning.
Financial KPIs every owner should track
| KPI | Definition | Why it matters |
|---|---|---|
| Gross margin % | (Revenue - direct costs) / Revenue | Pricing health and direct cost control |
| Operating margin % | Operating profit / Revenue | Overall profit conversion |
| Debtor days | Avg debtors / Revenue × 365 | Customer payment speed |
| Creditor days | Avg trade payables / COGS × 365 | Supplier payment speed |
| Inventory days (where applicable) | Avg inventory / COGS × 365 | Working capital tied in stock |
| Cash conversion cycle | Debtor days + Inventory days - Creditor days | Net working capital cycle |
| Current ratio | Current assets / Current liabilities | Short-term solvency |
| Cash runway (months) | Cash balance / Monthly cash burn | Time to financing event or breakeven |
Credit control to reduce debtor days
Active credit control turns a 60-day average payment cycle into 30-35. The mechanics:
- 1Clear payment terms on every invoice (Net 14, Net 30, etc.).
- 2Invoice promptly — same day or next day after work completion.
- 3Statement of account sent monthly to all customers with outstanding balances.
- 4Polite chase email at terms-due (e.g., on day 30 if Net 30).
- 5Phone call at terms+7 days.
- 6Formal late-payment letter at terms+14 days.
- 7Formal demand and interest under the Late Payment of Commercial Debts (Interest) Act 1998 at terms+30 days.
- 8For persistent non-payment: small claims court or legal proceedings.
What banks look for in your accounts
When applying for business finance, lenders review: profitability trend (3-year P&L), gross and operating margins, debt service coverage ratio, current ratio, director's drawings vs profitability, asset position, and aggregated liabilities. Clean, recent management accounts plus filed statutory accounts produce the best application. Hand-written or rough records substantially reduce the offer probability.
Break-even analysis
Break-even is the revenue level at which the business covers its costs. Calculation:
- 1Identify fixed costs per month (rent, salaries, insurance, software).
- 2Identify variable costs per unit/order (materials, direct labour, transaction costs).
- 3Calculate gross margin per unit/order (revenue - variable cost).
- 4Break-even revenue = Fixed costs / Gross margin %.
- 5Break-even units/orders = Fixed costs / Gross margin per unit.
Useful for new businesses (validating viability), pricing decisions, and capacity planning. The number changes as costs and prices change, so worth recalculating quarterly.
Management accounts for scaling
Beyond statutory annual accounts, growing businesses produce monthly management accounts. The standard contents:
- Profit and loss statement: actual vs budget vs prior year.
- Balance sheet: snapshot of assets, liabilities, equity.
- Cash flow statement: monthly inflows and outflows.
- KPI dashboard: gross margin, debtor days, cash runway, etc.
- Variance commentary: why the actuals differ from budget.
Cost: in-house £200-500/month of bookkeeper time, or outsourced via fractional CFO £500-2,000/month depending on complexity. Payback: management accounts catch problems in month 2 that without them would surface in month 6.
Cash flow forecasting or KPI tracking needed?
A Harrow specialist will set up the forecast, design the KPI dashboard, and put credit control on a structured rhythm. Free initial assessment.