Calculator · Economics scenario

CAC Payback Period Calculator

Contribution payback accumulates a cohort’s expected contribution until it covers acquisition cost. Match the acquisition costs to the acquired cohort and declare the margin, time basis and horizon. Cash payback also depends on billing and collection timing. A benchmark band alone does not determine affordability or the best acquisition policy.

Conditional scenario Model updated 2026-10-05

Formulas

Simple CAC Payback scenario

Payback_{months} = \frac{C A C}{( A C V /12 ) \times GM %}

Reads as: months of constant contribution per acquired customer to recover acquisition cost. CAC = acquisition spend matched to this cohort ÷ new customers acquired. Include the relevant acquisition costs and contribution costs consistently.

Cohort contribution Payback scenario

q = (N R R /100)^{1/12}, P = min {p : m = 1 \sum p (A C V /12) GM % q^{m - 1} \geq C A C}

Reads as: accumulate monthly expected contribution until acquisition cost is recovered. Annual cohort NRR is converted to a constant monthly revenue factor; the first month starts at the initial ACV. This is a scenario assumption, not an identified expansion or survival model.

Calculator

Acquisition spend matched to this cohort ($) New customers acquired (#) ACV per new customer ($) Contribution margin (%) NRR — net revenue retention (%) (annual cohort revenue factor)

CAC

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derived

Simple payback

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months

Cohort scenario

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months

Historical benchmark orientation

Stage	CAC Payback	Context
Short payback band	< 12 months	PLG with strong self-serve
Seed orientation	12–18 months	Early product-market fit
Series A orientation	18–24 months	Typical SaaS
Series B+ enterprise	24–36 months	Requires cohort evidence and sufficient cash
Long payback band	> 36 months	Assess the contribution path, cash and feasible alternatives

Historical 2024 reference: Bessemer Venture Partners and SaaS Capital. These bands are orientation; account for the target segment, cash timing and available capital.

What this scenario assumes

The scenario assumes the same cohort, a constant monthly revenue factor derived from annual NRR, a constant contribution margin and no change in service cost or price. It searches up to 120 months and interpolates the crossing within a month. Revenue-contribution payback differs from cash payback when billing, collections or payment timing differ. A cohort NRR observation does not establish that its factor persists for ten years.