What it means
Cash flows are uncertain. Receipts arrive later than planned, costs arrive earlier, and events that nobody forecast, from a major customer's failure to a pandemic, happen.
A business that holds exactly the cash it expects to need will run short as soon as reality departs from the plan, and the consequences of running short (penalty interest, lost supplier credit, distressed asset sales, missed payroll, insolvency) are far larger than the cost of holding a reserve. The cash cushion is the insurance.
Sizing it starts from the business's cash flow profile. A company with steady, diversified receipts and predictable costs needs less than one with lumpy contract payments or seasonal sales.
A company with a committed, undrawn bank facility can hold less cash than one without. A company whose costs can be cut quickly (variable staff, short leases) needs less than one with heavy fixed commitments.
The usual rules of thumb, three to six months of operating expenses for a small business, one to three months plus facilities for a larger one, are starting points to be adjusted by stress-testing: what happens to cash if sales fall 30% for six months, if the largest customer fails, if the bank does not renew the facility? The cushion must be real.
Cash held in a subsidiary that cannot remit it, cash pledged as security, cash earmarked for a tax payment next month, or cash that is in fact the peak of a seasonal cycle and will be consumed by the trough, is not a cushion. Treasurers separate the reserve from the operating balance, sometimes physically in a different account, and report it as a distinct figure so that it is not spent by default.
The cost is the return forgone. Cash in a current account earns little; in a deposit or money market fund it earns something; but a business with a 15% return on capital that holds $1 million idle is forgoing $150,000 a year.
Boards therefore debate the cushion's size, and shareholders of cash-rich companies press for the excess to be returned. The counter-argument is that the cushion's value appears only in the bad year, and that a company forced to raise money in a crisis pays far more than it saved by running lean.
Companies that entered the 2020 downturn with strong reserves emerged with market share; those that did not raised expensive capital or failed. The cushion also has a behavioural effect.
Managers with no reserve make short-term decisions: they delay investment, accept bad terms and spend time on cash rather than the business. A known reserve, with rules for when it may be used and how it is rebuilt, lets management run the business through normal variability without alarm and reserves the alarm for genuine crises.
In practice
Real-world examples.
Example
A software company holds 12 months of operating expenses in cash after a fundraising, so that a failed next round does not end the business.
Example
A restaurant group keeps two months of costs in a reserve account and rebuilt it over eighteen months after drawing it down during a forced closure.
Example
A listed retailer holds $2 billion of cash and faces shareholder pressure to return half of it, arguing that the reserve let it keep investing through the last recession.
Think of it
“A cash cushion is your financial shock absorber-extra padding to smooth out bumps in the road.
Formula
Calculation
Cash Cushion = Cash and equivalents + Committed undrawn facilities minus Operating cash requirement minus Restricted and committed cash
Months of Cover = Cash cushion / Average monthly operating cash outflow
Target Cushion = Largest cumulative cash shortfall in the stress scenario + Safety margin
Worked example. A specialist engineering company has monthly operating cash outflows of $850,000 (of which $500,000 is payroll), monthly receipts averaging $950,000 but ranging from $600,000 to $1,400,000 depending on project milestones, cash of $1,900,000, an undrawn committed facility of $500,000, and a $300,000 tax payment due next month.
Operating requirement: the finance director estimates the working balance needed to absorb ordinary timing differences at $600,000 (roughly the largest week-to-week dip seen in the past two years).
Cushion = $1,900,000 + $500,000 minus $600,000 minus $300,000 = $1,500,000
Months of cover = $1,500,000 / $850,000 = 1.8 months
Stress test 1: the largest customer (25% of receipts) delays payment for three months. Cumulative shortfall = $950,000 x 25% x 3 = $712,500. The cushion covers it.
Stress test 2: a downturn cuts receipts by 35% for six months while costs fall only 15% (fixed leases and retained skilled staff). Monthly shortfall = ($950,000 x 0.65) minus ($850,000 x 0.85) = $617,500 minus $722,500 = minus $105,000 a month, cumulative $630,000 over six months. Covered.
Stress test 3: both together: a $712,500 delay in the first three months on top of the downturn shortfall. Cumulative low point about $1,030,000. Covered, with $470,000 to spare.
Stress test 4: the bank withdraws the facility at renewal in month 4 during the combined scenario. Cushion falls by $500,000 to $1,000,000 against a $1,030,000 low point: a shortfall of $30,000. The board sets a target cushion of $1,750,000 (the combined scenario plus a margin, without reliance on the facility), to be reached by retaining $250,000 of the next year's profit rather than distributing it, and adopts a rule that the reserve may be drawn only with board approval and must be rebuilt within twelve months.
Cost of the cushion: $1,750,000 held in a money market fund at 4% earns $70,000; the company's return on capital is 14%, so the opportunity cost is about $175,000 a year. The board judges the insurance worth it against a business whose failure mode is a missed payroll for 60 skilled staff.Case study
Seen in the real world.
Two logistics companies of similar size entered a sudden downturn in which freight volumes fell 40% for five months. The first had run with cash at the minimum for years, distributing every surplus to its owners, and relied on an overdraft that its bank had always renewed. When volumes fell, the overdraft was fully drawn within six weeks, the bank declined to extend it, and the company laid off a third of its drivers, sold four vehicles at a loss to a competitor, and lost two contracts because it could not guarantee capacity.
When volumes recovered, it could not hire drivers back fast enough and took two years to return to its previous size. The second company had held a reserve of three months' costs, a policy its founder had adopted after a near-failure a decade earlier and which its owners had grumbled about ever since. It kept its drivers, took on the first company's two contracts, bought the four vehicles, and came out of the downturn 20% larger.
The owners stopped grumbling. Its finance director's board paper afterwards calculated that the reserve had cost about $120,000 a year in forgone returns over the decade and had, in one year, been worth several million dollars of market share and avoided losses. The paper's title was "The cheapest insurance we have ever bought".
Watch out
Common mistakes.
- Counting restricted, trapped or committed cash, or the seasonal peak balance, as a cushion.
- Relying entirely on an uncommitted overdraft as the cushion. Facilities that can be withdrawn on demand are least available when most needed.
- Never using the reserve because it has become sacred, or using it for routine shortfalls because it is there. Set rules for drawing and rebuilding it.
Questions
People also ask.
How large should a cash cushion be?
Enough to cover the largest plausible stress scenario with a margin. Rules of thumb are three to six months of operating expenses for small businesses; larger companies size it by stress-testing and may hold part as committed facilities.
Is holding a cash cushion a waste of capital?
It has a cost in forgone returns. The question is whether that cost is less than the expected cost of running short, which for most businesses it is.
Where should the cushion be held?
Somewhere safe, liquid and separate from operating cash: an instant-access deposit, a money market fund, or short-term government securities, in the company's own name and not pledged.
From the founder's library
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