Liquidity management is the discipline of making sure a business always has enough cash, or immediately available funding, to pay its debts as they fall due. Those words matter, because the Insolvency Act 1986 treats a company as unable to pay its debts if it cannot meet them as they fall due, however profitable it is on paper. To improve liquidity, you forecast cash weekly, collect faster, hold less stock, plan for tax payments and arrange funding before you need it.
Liquidity, profit and solvency are different tests
A profitable company can run out of cash. Profit is recognised when a sale is made, but cash arrives only when the customer pays. Meanwhile, stock, wages, VAT and loan repayments go out on their own timetable. Growth widens the gap, because each new sale needs working capital before it produces cash.
Section 123 of the Insolvency Act 1986 sets out when a company is deemed unable to pay its debts. Directors should keep the two main tests in view, and know how a creditor can trigger the deeming rule:
- The cash-flow test. The company is unable to pay its debts as they fall due. This is the liquidity test;
- The balance-sheet test. The value of the company's assets is less than its liabilities, taking into account contingent and prospective liabilities;
- The statutory demand. A creditor owed more than £750 by the company can serve a written demand, and if the company neglects to pay, secure or settle it for three weeks it is deemed unable to pay its debts.
Liquidity management means seeing the first test coming months in advance, rather than discovering it when a supplier serves a demand.
Measuring liquidity
Balance sheet ratios give a quick reading, but the cash forecast is what you manage against.
- Current ratio. Current assets divided by current liabilities. Below 1.0 means short-term obligations exceed short-term resources;
- Quick (acid-test) ratio. The same calculation with stock excluded, because stock has to be sold and then collected before it becomes cash;
- Headroom. Cash plus undrawn committed facilities, less the lowest forecast balance over the next 13 weeks. This shows how much room the business actually has;
- Cash conversion cycle. Debtor days plus stock days less creditor days, which tells you how long each pound is tied up in operations.
Worked example. A distributor has £400,000 of current assets, of which £180,000 is stock, and £320,000 of current liabilities. The current ratio of 1.25 looks comfortable. The quick ratio of 0.69 does not. If a quarterly VAT payment, the payroll and a large supplier run all fall in the same week, the business may hit its overdraft limit while its balance sheet still shows net current assets. Only a weekly forecast shows this.
Forecast weekly, review monthly
The core tool is a rolling 13-week cash forecast, updated every week and compared with what actually happened. Behind it sits a 12-month monthly forecast that catches seasonal troughs, annual bills and loan repayments. Our guides to cash flow monitoring and building a cash flow forecast set out the structure. Two habits make the forecast reliable. The first is to base receipts on how customers actually pay, not on the invoice due date. The second is to record every fixed-date outflow, especially tax, before you forecast anything else.
How to improve liquidity
The cheapest liquidity comes from inside the business:
- Collect faster. Invoice on completion, agree terms in writing and chase before the due date. Where no payment date is agreed, a business-to-business payment becomes late 30 days after the invoice or delivery. Agreed terms longer than 60 days must be fair to both parties;
- Use your statutory rights. On a late business debt you can claim statutory interest at 8% over the Bank of England reference rate, plus fixed compensation of £40, £70 or £100 depending on the size of the debt. Statutory interest is not available where the contract sets its own interest rate;
- Release stock. Identify slow-moving lines and stop re-ordering them. Stock that sits on the shelf is cash you have already spent;
- Manage payables openly. Negotiate longer terms rather than paying late, because late payment invites interest claims and tighter credit limits;
- Arrange facilities early. Lenders offer the best terms to businesses that do not need the money yet. A committed facility or invoice finance arranged while trading is strong is far easier to obtain than one requested during a squeeze.
Our guide to working capital optimisation covers each lever in more depth.
Tax is a predictable cash event, so plan for it
Tax payments are large, fixed-date and easy to forecast, yet they cause many liquidity crises:
- Corporation tax. Due 9 months and 1 day after the end of the accounting period where taxable profits are up to £1.5 million. Above that, it is normally paid in quarterly instalments, two of them before the year end. The £1.5 million threshold is divided between associated companies;
- VAT. Usually due one calendar month and 7 days after the end of the VAT period;
- PAYE and National Insurance. Due by the 22nd of the next tax month when paid monthly and electronically.
HMRC is not cheap credit. Late payment interest on corporation tax, income tax, National Insurance and VAT has run at the Bank of England base rate plus 4% since 6 April 2025, and penalties can apply on top. If a payment genuinely cannot be met, contact HMRC before the deadline to ask for a payment plan (Time to Pay). HMRC will check that the plan is affordable before agreeing to it.
When a liquidity problem becomes a directors' problem
Once a company's cash position deteriorates, directors carry personal exposure. Under section 214 of the Insolvency Act 1986, a court can order a director to contribute to the company's assets if the company goes into insolvent liquidation and, at some earlier point, the director knew or ought to have concluded that there was no reasonable prospect of avoiding it. A current, documented cash forecast and minuted board decisions are the best evidence that directors acted on the information available. If the forecast shows a shortfall that the levers above cannot close, take advice early. You have more options at that stage.
Sources: Insolvency Act 1986, section 123; Insolvency Act 1986, section 214; GOV.UK: late commercial payments; Late Payment of Commercial Debts (Interest) Act 1998, section 5A; GOV.UK: pay Corporation Tax; Taxes and Duties (Interest Rate) Regulations 2011, regulation 3; GOV.UK: if you cannot pay your tax bill on time.
Acumon builds rolling cash forecasts as part of management accounts and financial modelling work, and our interim CFOs step in when a business needs liquidity managed week by week.