SaaS

How to Calculate CAC Payback Period

Payback answers how many months of gross profit it takes to earn back what you spent to win a customer—use gross profit here, not top-line revenue alone.

Keep inputs in sync

Use CAC covering the same new customers you counted for gross profit.

Use monthly gross profit as ARPU times margin—or type profit directly.

Expansion speeds real life

Upsells can shorten lived payback even when this simple view stays flat.

Say so in conversations—don't assume everyone sees expansion in the spreadsheet.

Cross-check multiples

Pair payback reads with LTV:CAC when someone wants to crank spend prematurely.

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