Customer acquisition cost

Measure the fully defined acquisition spend required for each new customer and track it by cohort, channel and payback period.

Quick answer

Customer acquisition cost, or CAC, measures the acquisition costs incurred for each new customer under a stated cost and customer definition. Depending on the business, the numerator may include media, sales compensation, incentives, agency fees, partner revenue share and acquisition-related support costs.

Use the worked example

Meaning and transaction use

An SEC-filed presentation calculates annual-cohort CAC as marketing spend plus incentives divided by new users for the period. [S1]

An SEC-filed company report defines CAC using direct marketing, revenue share, retention, renewal, copywriting, marketing, telesales and commission costs. [S2]

Proposed control method: publish a CAC dictionary and reconcile channel-level spend to finance and acquired-customer records.

Worked example

Illustrative quarterly CAC only. Assume 1.2 million of defined acquisition spend and 4,000 new paying customers.

Scroll the table horizontally to view all columns.

Measure	Calculation	Result
Acquisition spend	Given	1.2m
New paying customers	Given	4,000
CAC	1,200,000 / 4,000	300
Customers at 1.5m spend and same CAC	1,500,000 / 300	5,000

Illustrative CAC is 300 per new paying customer under the stated cost and customer definitions.

Proposed transaction review process

Define CAC

Set included costs, customer event, period and channel.

Reconcile inputs

Tie spend to finance and customers to product or billing records.

Analyse cohorts

Compare channel, segment, geography, payback and retention.

Act on economics

Reallocate spend using marginal CAC, LTV and capacity evidence.

Evidence checklist

Spend

Media, commissions, payroll, incentives, agency and partner costs.

Customers

Qualified, activated and paying-customer records.

Attribution

Channel, campaign, timing and multi-touch methodology.

Economics

Gross margin, retention, LTV and payback analysis.

Decision framework

Situation	Proposed action
Channels use different definitions	Restate them on one comparable basis.
CAC rises with scale	Test marginal economics before expanding spend.
Sales cycles are long	Lag spend and cohorts consistently.
Organic acquisition grows	Report blended and paid CAC separately.

Common errors to check

Dividing spend by leads instead of the defined customers.
Excluding material sales costs without disclosure.
Mixing spend and customer periods.
Optimising CAC without retention or margin.

Reconcile acquisition economics

Bring acquisition spend, customer cohorts and channel attribution to a CAC review. Standardise definitions and test marginal payback.

Discuss the transaction

Primary references and editorial scope

SEC filing: Cohort CAC calculation
Example CAC as marketing spend plus incentives divided by new users. Reference checked 17 September 2026.
SEC filing: Detailed CAC cost definition
Example direct marketing, revenue share, retention, renewal, payroll and commission cost perimeter. Reference checked 17 September 2026.

Editorial qualification

General transaction education using public United States filings. Figures are hypothetical. CAC is a non-standard operating metric whose definition can differ by company.

General business information. Obtain advice appropriate to the legal, tax, accounting and financing facts. No offer, lender commitment or transaction outcome is represented. All worked examples use expressly assumed figures. Editorial draft date: 17 September 2026.