Building a Cash Reserve: How Much Is Actually Enough

A cash reserve is the money set aside specifically to cover the business's operating expenses if revenue drops or stops for a while — a slow season, a lost major customer, an unexpected repair. Without one, a single bad month can force decisions no owner wants to make under pressure, like laying off staff or missing a loan payment.

A commonly cited rule of thumb is three to six months of operating expenses in reserve, but the right number for a specific business depends on how predictable its revenue actually is. A business with seasonal swings or a handful of large customers needs more cushion than one with steady, diversified, recurring revenue.

The reserve should cover real operating expenses — rent, payroll, essential recurring costs — not revenue. It's sized against what you'd need to keep the lights on and the team paid through a rough patch, not against what you'd normally bring in.

Building it doesn't require a dramatic sacrifice; a modest, consistent percentage of revenue set aside automatically every month — even 2 to 5 percent to start — adds up meaningfully over a year or two without meaningfully starving day-to-day operations.

Keep the reserve in a separate account, ideally one that's slightly less convenient to access than your main operating account. The friction is the point — it keeps the money from quietly getting absorbed into regular spending the moment it builds up.

A reserve isn't meant to sit untouched forever regardless of circumstances — it's meant to be used when a real, serious dip in revenue actually happens, and then rebuilt afterward. Treating it as untouchable defeats the purpose just as much as spending it on ordinary expenses would.