What is the formula for customer acquisition cost?

CAC equals total acquisition cost in a period divided by the number of new customers acquired in that period. A fully loaded version includes media, sales and marketing salaries, commissions, agencies, software, and partner payouts. For long sales cycles, divide an earlier period's spend by the current period's customers so cost and results line up.

What is the difference between blended CAC and paid CAC?

Blended CAC divides all acquisition cost by all new customers, including organic and word of mouth. Paid CAC divides paid media spend by customers attributed to paid channels only. Blended shows the company-wide cost of growth; paid shows what advertising costs per customer. Reporting only blended can hide a paid channel whose costs are rising.

Should salaries be included in the CAC formula?

Yes, in fully loaded CAC. Sales and marketing salaries, benefits, and commissions are usually the largest acquisition cost in B2B, and leaving them out can make CAC look a fraction of its true size. A media-only figure is still useful for comparing campaigns, as long as it is labelled clearly and never compared with LTV.

How do you calculate CAC for an affiliate or partner program?

Add commissions, bonuses, partner software, and the time of the people who manage partners, then divide by the number of paying customers partners sourced in the same period. Decide how recurring commission is handled, either inside partner CAC or as lower margin in LTV, and count paying customers rather than signups in the denominator.

Customer Acquisition Cost Formula: Variants and a Worked Example

The customer acquisition cost formula is total acquisition cost in a period divided by new customers acquired in that period. This page works the arithmetic; [what CAC means](/learn/what-is-customer-acquisition-cost) covers what belongs in the spend figure and why the number matters. Paid CAC counts only ad spend and paid customers; blended CAC uses all customers; fully loaded CAC adds salaries, tools, agencies, and partner commissions. Calculate it per channel and state which version you report.

The base formula

CAC = total acquisition cost in a period / new customers acquired in that period.

Every variant below keeps that shape. What changes is the numerator (which costs count), the denominator (which customers count), and the timing (whether the spend and the customers come from the same period). Most disagreements about CAC are really disagreements about those three choices, so state them next to the number every time it is reported.

Four formula variants

The same quarter can produce very different CAC figures depending on which version is used.

Paid CAC

Paid CAC = paid media spend / customers attributed to paid channels. It isolates what advertising costs per customer and is useful for comparing campaigns. It leaves out the people, tools, and agencies that make the ads work, so it always looks cheaper than the true cost of growth.

Blended CAC

Blended CAC = all acquisition cost / all new customers, including those from organic search, word of mouth, and direct traffic. It is the company-level number investors often ask for. Because free channels sit in the denominator, a strong organic month can hide a paid channel that is getting more expensive.

Fully loaded CAC

Fully loaded CAC puts everything in the numerator: media, sales and marketing salaries and benefits, sales commissions, agencies and contractors, software, content, events, partner commissions and partner team time, and often a share of overhead. It is the most honest view of what a new customer costs, and the right input for LTV to CAC and payback.

Lagged CAC

Lagged CAC divides spend from an earlier period by customers won in the current one, so that spend and the customers it produced line up. If deals take about a quarter to close, last quarter's spend over this quarter's new customers gives a fairer figure than matching the same quarter.

A worked example (illustrative numbers)

Take one illustrative quarter for a B2B software company. The figures are invented to show the arithmetic, not benchmarks.

Costs: paid media $60,000; marketing salaries $90,000; sales salaries and commissions $150,000; agency fees $25,000; sales and marketing software $15,000; partner commissions $30,000; partner manager time allocated to the program $20,000. Total: $390,000.

New customers: 150 in total, of which 60 are attributed to paid channels, 25 to partners, and 65 to organic, direct, and outbound.

Paid media over all customers: $60,000 / 150 = $400. This is the number that flatters, and it is not a real CAC.
Paid CAC: $60,000 / 60 = $1,000.
Fully loaded blended CAC: $390,000 / 150 = $2,600.

The same quarter supports a CAC of $400, $1,000, or $2,600. Only the last one tells you what growth actually costs.

CAC by channel, including partner CAC

Channel CAC assigns costs and customers to each source: channel cost (direct spend plus the people and tools that serve it) / customers attributed to that channel. The attribution rule decides the denominator, so use the same rule for every channel.

Partner CAC = (partner commissions + bonuses and incentives + partner software + partner team time) / partner-sourced customers. In the example: ($30,000 + $20,000) / 25 = $2,000, before any share of software. The paid channel, loaded with its agency fees and an assumed half of marketing salaries, comes to ($60,000 + $25,000 + $45,000) / 60, about $2,167. Sales salaries still need allocating across channels, which is where most channel CAC debates start.

Two partner-specific choices matter. First, recurring commission: a partner paid a share of every renewal costs more over the customer's life than at signup. Either count expected commission over the customer lifetime in partner CAC, or treat ongoing commission as a reduction in that customer's margin inside LTV, but do one or the other, never both and never neither. Second, the denominator should be partner-sourced paying customers, not signups. Programs that bind the referral code to the account at signup, as HyypeFi does, make that count straightforward because every later payment carries the partner's identifier.

Common formula mistakes

Counting trials or free signups as customers, which shrinks CAC until they fail to convert.
Mixing periods without lagging, which makes CAC fall in fast-growth quarters and spike in slow ones for reasons unrelated to efficiency.
Including expansion revenue customers. CAC is for new customers; upsells to existing accounts have their own cost.
Leaving out commissions because they are paid later or by a different team.
Reporting blended CAC alone, which hides channel saturation behind organic growth.

Turning CAC into payback

CAC payback months = CAC / (monthly revenue per new customer x gross margin). With the illustrative $2,600 fully loaded CAC and a customer producing $250 of monthly gross profit, payback is 2,600 / 250 = 10.4 months. Payback converts CAC into a cash question: how long the business funds each new customer before it is earned back. Calculate it by channel, because partner and paid customers often pay and retain differently.

Frequently asked questions

What is the formula for customer acquisition cost?: CAC equals total acquisition cost in a period divided by the number of new customers acquired in that period. A fully loaded version includes media, sales and marketing salaries, commissions, agencies, software, and partner payouts. For long sales cycles, divide an earlier period's spend by the current period's customers so cost and results line up.
What is the difference between blended CAC and paid CAC?: Blended CAC divides all acquisition cost by all new customers, including organic and word of mouth. Paid CAC divides paid media spend by customers attributed to paid channels only. Blended shows the company-wide cost of growth; paid shows what advertising costs per customer. Reporting only blended can hide a paid channel whose costs are rising.
Should salaries be included in the CAC formula?: Yes, in fully loaded CAC. Sales and marketing salaries, benefits, and commissions are usually the largest acquisition cost in B2B, and leaving them out can make CAC look a fraction of its true size. A media-only figure is still useful for comparing campaigns, as long as it is labelled clearly and never compared with LTV.
How do you calculate CAC for an affiliate or partner program?: Add commissions, bonuses, partner software, and the time of the people who manage partners, then divide by the number of paying customers partners sourced in the same period. Decide how recurring commission is handled, either inside partner CAC or as lower margin in LTV, and count paying customers rather than signups in the denominator.