Petty cash budget: limits, replenishment and variance

A petty cash budget sets period limits for a company's small, permitted expenses by category or department. Build it from supported expense history and known operating needs, then compare the receipts with the approved allowance. Keep that spending budget separate from the cash float held by the custodian.

Separate the spending allowance from the cash float

The monthly budget answers how much the company authorizes for eligible expenses. The float answers how much physical cash the custodian holds between replenishments. The same float can fund repeated cycles of spending during a month.

Under a fixed-fund arrangement, cash remaining plus valid unreplenished vouchers should equal the authorized float. The IRS illustrates this petty cash method in Publication 583: attach supporting receipts to petty cash slips and replenish the amounts represented by those slips. Its example is a recordkeeping illustration, not a universal spending limit.

The company policy should identify the custodian, permitted purchases, approval authority, documentation requirements and handling of exceptions. Keep payroll, employee loans and ordinary supplier payments outside the fund unless the company's authorized process explicitly permits them. Use the broader cash budget for company-wide receipts and payment planning.

Set the budget from the expense register

Start with an export of completed petty cash vouchers. Keep voucher ID, purchase date, amount, category, department, approver, receipt reference and replenishment reference. Separate actual business expenses from fund transfers and unresolved advances.

Use comparable periods. A temporary office move should not become a recurring allowance simply because it appeared in the latest month. Check whether purchasing cards or central purchasing have already replaced some cash purchases.

This US distribution company's register gives the following history. Dollar amounts are exact; the averages require no rounding.

The October shipping allowance increases by $20 for a documented mailing requirement. Supplies and errands retain their historical averages. Management separately authorizes a $60 reserve that requires approval before use. The proof is $520 historical average + $20 planned increase + $60 reserve = $600.

For a worksheet with the monthly history in B through D, calculate the category average in E2 and fill down:

=AVERAGE(B2:D2)

Do not let blank cells silently mean missing history: identify whether an empty month means no expense or an incomplete register. Enter a confirmed zero when there was no spending.

Size the float for the replenishment cycle

The company authorizes a $300 float, separate from the $600 October expense allowance. The custodian records the following complete cycle history, with each replenishment supported by the receipts from that cycle:

The float supports $530 of spending because $380 has been replenished during the month. At closing, $150 cash + $150 outstanding vouchers = $300. The expense register also reconciles: $380 already replenished + $150 unreplenished expenses = $530.

Set the float with reference to expected spending between replenishments and the time approvals take. Increasing it does not increase the approved monthly expense budget. If the register repeatedly shows cash shortages before valid replenishments arrive, first check timing and policy compliance instead of assuming a bigger monthly allowance is needed.

For the transaction-level layout and supporting documents, use the separate petty cash report guide. The cash budget template addresses the broader payment schedule.

Compare expenses with category and department limits

October's supported expenses produce this review. A positive variance means spending above the allowance; a negative amount means spending below it.

With budget in B and actual in C, the variance formula is:

=C2-B2

The company is $70 below its total allowance, but shipping and supplies exceed their own limits. Unused reserve is authorization remaining, not an expense saving achieved through operational improvement. Report category breaches even when the total budget remains sufficient.

The supplies category also has an approved department split:

Operations spent $175 against $160, while administration spent $80 against $90. Their actuals sum to $255; the departmental variances of $15 and −$10 sum to the category's $5 overrun. That tie points to an owner without changing the company total. The general variance analysis guide covers broader reporting conventions.

Where it goes wrong

• Transfers treated as expenses. Initial funding and replenishment move cash. Counting them alongside the same vouchers duplicates spending.
• Unsupported purchases accepted as complete. The IRS recordkeeping guidance explains the role of receipts and other supporting documents. An approval alone does not describe what was bought.
• Cash differences buried in categories. If the closing count were $145 against the $150 expected cash, the fund would be $5 short: $145 + $150 vouchers = $295. Investigate and record the approved treatment separately.
• Unused limits automatically carried forward. A monthly allowance does not establish authority to accumulate spending rights indefinitely. Follow the company's approval period and carryforward policy.

Review your petty cash budget in Covirage

Bring the voucher export, approved department limits and replenishment register to Covirage. Its tools map columns, compute spending variances and check the reconciliations; the external AI model explains the results with every figure traced to its rows. Create a free Covirage account and bring a sample of your own data.

See cost variance analysis for the supporting business use case.