Fixed costs per month

€

Staff, rent, leasing, insurance, software, interest and repayments.

How much does your revenue fluctuate?

littlemoderatelystrongly, seasonal

Average payment term of your customers

days

Revenue share of your largest customer

%

Large payments in the next twelve months

€

Tax back payments, annual fees, one-off payments, planned purchases.

036912 months

Recommended buffer: …
Base reserve: …
Provision for large payments: …
Total reserve: …
Set aside monthly for large payments: …

Guidance based on a transparent model, not advice. Three to six months of fixed costs are often cited; your figure depends on your industry, contracts and financing. A credit line is a second line of defence and deliberately not included here.

How the tool calculates

Base value by revenue volatility: little three, moderate four, strong six months of fixed costs.
Payment terms: every 30 days add half a month, because the money is tied up in open invoices for that long.
Concentration: if the largest customer accounts for more than 20 per cent of revenue, add half a month for every 10 percentage points, at most two months.
Large payments in the next twelve months form a separate provision and are added to the base reserve.

Why a reserve

A cash reserve bridges periods in which less money comes in than goes out: seasonal lulls, late payments, a lost order or an investment that only pays off later. It protects against expensive emergency solutions and creates room to act.

How to use the result

Take the figure as a reasoned starting point for your own planning. Check it against a rolling 13-week cash flow forecast and discuss larger deviations with your tax adviser or your bank.

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