Customer Acquisition Cost
Fully-loaded sales-and-marketing (S&M) expense incurred to acquire one new customer during the period. Per the SMSB standard, the CAC numerator includes salaries + commissions + benefits + travel + marketing programs + tooling — i.e. all S&M costs, not just direct-attribution paid acquisition. The denominator is new logos, not deals. Common pitfall: omitting fully-loaded comp (especially BDR/SDR base salary and CS-team cost-of-sale where they participate in expansion) understates CAC and inflates every downstream efficiency metric. The board cares about CAC alongside CAC Payback and the CAC Ratio family — single-number CAC is a building block, not a verdict. — Sales KPI anchored to SaaS Metrics Standards Board.
Rogue ID: sales.cac
Type: Currency
Domain: Sales
Definition
Fully-loaded sales-and-marketing (S&M) expense incurred to acquire one new customer during the period. Per the SMSB standard, the CAC numerator includes salaries + commissions + benefits + travel + marketing programs + tooling — i.e. all S&M costs, not just direct-attribution paid acquisition. The denominator is new logos, not deals. Common pitfall: omitting fully-loaded comp (especially BDR/SDR base salary and CS-team cost-of-sale where they participate in expansion) understates CAC and inflates every downstream efficiency metric. The board cares about CAC alongside CAC Payback and the CAC Ratio family — single-number CAC is a building block, not a verdict.
Formula
CAC = Total fully-loaded S&M expense for the period / New Customers Added in the period. Per SMSB §CAC: numerator includes all S&M spend (compensation, benefits, programs, tooling, allocated overhead); denominator counts net-new logos only (not expansion deals).Why it matters
The cost side of the customer-unit economics ledger — paired with ACV and gross margin, determines whether each customer is a profitable transaction over a reasonable horizon. Boards read CAC alongside payback period before debating S&M investment levels.
How to interpret
Absolute CAC values vary by ACV band — what matters is the ratio CAC / first-year-ARR (= New CAC Ratio) and CAC Payback. Per public SaaS comps, healthy CAC payback is < 24 months gross-margin-adjusted; > 36 months usually means the acquisition motion is either too expensive or the contract terms too short.
Calculation policy
How an AI agent should compute this KPI from messy company data. Free-text rules consumed at reasoning time — not a deterministic DSL. The most common ways to get this wrong are listed under Common miscomputations.
Inclusion rules
- Numerator: total fully-loaded S&M expense for the period — all sales + marketing compensation (base, commission, benefits), marketing programs, sales/marketing tooling, travel, allocated S&M overhead.
- Denominator: count of net-new logos acquired in the same period (
sales.new_customers_added). - Result is a per-customer dollar figure.
Exclusion rules
- R&D, G&A, and COGS — CAC is S&M-only.
- Expansion-attributed S&M / CS cost — that belongs in
sales.expansion_cac_ratio. If AEs do both, allocate by a documented rule. - Expansion deals in the denominator — count new logos only.
- Stock-based compensation if the company reports cash CAC (disclose which basis is used).
Required inputs
- Fully-loaded S&M expense for the period.
- New logos acquired in the same period.
- If AEs split new vs expansion: the documented allocation rule (e.g. fraction of OTE tied to new-business quota).
Data-source priority
- Audited or reviewed financials for S&M expense.
- CRM for new-logo count, matched to the same period boundary.
Edge cases
- CAC-lag: S&M spent this quarter often acquires customers next quarter. For long sales cycles, consider a trailing-spend window (e.g. lag S&M by the average sales-cycle length) and disclose the method.
- Founder-led sales with no formal S&M line: impute a market-rate cost or flag CAC as not-yet-meaningful — never report a near-zero CAC.
- Marketing brand spend that benefits future periods: include it in the period spent; do not capitalize it.
Validation checks
- CAC is positive.
- CAC ÷ first-year ACV ≈ New CAC Ratio — cross-check the two.
- CAC at a > $5M ARR company that comes out implausibly low (e.g. < $1k for a $30k-ACV product) almost always means S&M is not fully loaded.
Common miscomputations
- Omitting fully-loaded comp — especially SDR/BDR base salary, sales-ops, and sales-engineering — understates CAC and inflates every downstream efficiency metric.
- Counting expansion deals in the denominator — makes the new-logo motion look cheaper than it is.
- Using only paid-media spend ("ad CAC") and calling it CAC — ignores the much larger people cost.
- Period mismatch: S&M from one period, new logos from another. For long cycles this is defensible only if explicitly lag-adjusted and disclosed.
- Dividing by deal count instead of distinct new logos — multi-deal customers inflate the denominator and understate CAC.
Related KPIs
sales.cac_payback_periodsales.new_cac_ratiosales.blended_cac_ratiosales.expansion_cac_ratiosales.new_businesssales.new_customers_added
Source
SaaS Metrics Standards Board · section: CAC — published 2023-01-01.
Why does this cite SaaS Metrics Standards Board? Read the ontology methodology for the published vs editorial tier system, attribution rules, and dispute process.
Metric definitions reference standards published by the SaaS Metrics Standards Board (saasmetricsboard.com). imboard is not affiliated with, endorsed by, or a member of SMSB.
Stage relevance
| Company stage | Priority |
|---|---|
| Series A | Core |
| Series B | Core |
| Series C+ | Core |
| Public | Core |
Suggested for stages: Series A, Series B, Series C+, Public.
Default owning functions
- Sales
- Finance
Machine-readable
- This KPI as JSON:
/api/ontology/sales/cac.json - All Sales KPIs:
/api/ontology/sales.json - Full catalog:
/api/ontology/index.json
Blended CAC Ratio
Total fully-loaded S&M spend in the period divided by the dollars of new CARR generated in the period (new-customer + expansion CARR combined). Per the SMSB standard, the headline efficiency ratio for the full sales-and-marketing motion — answers "how many cents do we spend on S&M to add one dollar of contracted ARR." Common pitfall: blending without separately reporting New CAC Ratio and Expansion CAC Ratio hides which side of the motion is driving efficiency — for a healthy SaaS company expansion CAC is usually 3–5× cheaper per dollar than new-logo CAC. — Sales KPI anchored to SaaS Metrics Standards Board.
CAC Payback Period
Number of months required for the gross profit generated from a new customer's ARR to recover the fully-loaded S&M spend used to acquire them. The single most decision-useful efficiency metric at the board level — it directly connects acquisition cost, ACV, and gross margin into one "how long until we break even on this customer" answer. Per the SMSB standard, the calculation must use gross-margin-adjusted ARR in the denominator (not raw ARR) to be cross-company comparable. Common pitfall: using raw ARR understates payback by ~25–30 percentage points and breaks comparability with peer benchmarks. — Sales KPI anchored to SaaS Metrics Standards Board.