Cash Reserve Formula for Payroll, Taxes, and Deposits

The reserve starts with weekly fixed costs

Before an emergency hits, decide how much cash to keep in the bank. Use weekly fixed costs × target weeks, and plan the drain order: payroll, taxes, deposits.

Write down the cash that has to leave the bank no matter how slow the week is. Rent, payroll, loan payments, software, insurance, and recurring supplier bills belong here. One-time costs do not. Finish with a single weekly number you can defend without guessing.

Some costs move with sales. If a supplier bill rises when you take a big order, it is not fixed. Keep it out of the base number. If a cost is steady even when revenue is flat, it belongs in the base number. The reserve covers the bills that stay the same when sales fall.

Call that number your weekly fixed costs. It is the base for the reserve. Keep the balance in a separate account you can check before each payroll.

Most businesses should hold 8 to 13 weeks

Eric Trettel, a small business accountant and bookkeeper, advises most businesses to hold a reserve equal to at least 8 to 13 weeks of operating expenses. That range gives room for a slow period, a tax bill, and a deposit without borrowing in a hurry.

Bluevine's survey sampled 774 U.S. owners with annual revenue between $50,000 and $5 million. In that survey, 38.7% of owners lacked cash sufficient to pay one month of operating expenses if an emergency occurred. The formula closes that gap.

Pick a target that matches your risk. If revenue is steady and customers pay on time, start near the lower end of the advised weeks. When revenue swings, customers pay slowly, or costs are high, move toward the higher end. The target is a floor.

Write the target next to the weekly number. If you change the target, recalculate the reserve. The number should match your plan.

The drain order is payroll, taxes, deposits

• Calculate weekly fixed costs. Add rent, payroll, loan payments, insurance, software, and recurring supplier bills. Finish with a single weekly number, not a vague average.
• Multiply that number by your target weeks. End with a dollar amount you can park in a separate account.
• Label the reserve. Write the purpose on the account or in your cash plan: payroll, taxes, deposits. Keep it separate from day-to-day cash.
• Set the drain order. Write payroll, taxes, deposits in that order. Keep the rule visible when the bank balance drops.

The common mistake is to size the reserve from average revenue. A slow week can make that number look safe when it is not. Review the reserve at the same time you review payroll. If the number has dropped, decide before the next bill whether to rebuild it or reduce spending. If you rebuild, do it on a set schedule.

Payroll is the first claim on the reserve, because a payroll squeeze is the fastest way to lose trust. 51.3% of owners said a payroll squeeze would lead them to use emergency funds within 48 hours to cover payroll. If your reserve is thin, that is the first place it will go.

Tax deadlines are fixed even when revenue is low. 40.4% of owners said an upcoming tax deadline would prompt them to act on cash reserves. A late tax payment can create extra costs, so the reserve should cover it before it becomes a problem. Set aside the amount you expect to owe before you spend the rest.

Deposits are the last claim, and they can protect a good order from becoming a cash-flow problem. 36.4% of owners said a large, unexpected order that required a deposit would lead them to act. Covering it without borrowing lets you keep the order. If you cannot, you may need to decline it.

This article is general information, not tax or financial advice. Consult a qualified professional about your situation.