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Contribution Margin

Unit Economics·4 min read·May 2026

Contribution margin is revenue minus the costs that vary directly with each sale — cost of goods sold, payment processing, shipping, and in Exactius's framework, the media spend required to acquire that sale. It is the metric that determines whether a growth system is generating real value or just moving revenue through the business at a loss.

Definition

Revenue is a vanity metric when viewed in isolation from costs. A brand generating $10M in revenue while spending $4M on COGS, $1M on shipping, and $5M on media is not growing — it is sustaining an expensive revenue cycle with zero margin for fixed cost coverage or profit. Contribution margin makes this visible: it tells you what is actually left after the variable costs of generating each sale.

There are two common definitions: Contribution Margin 1 (CM1) deducts COGS from revenue. Contribution Margin 2 (CM2) further deducts variable marketing costs — the media spend allocated to acquiring that customer. CM2 is the number Exactius uses because it captures the full variable cost of generating a sale, including the acquisition investment.

Exactius uses CM2 as the governing profitability metric in the Growth Operating System, replacing ROAS and revenue growth as the primary success signals. A channel that drives high ROAS but low CM2 — because of high COGS, high returns, or low average order value — is less valuable than a channel with lower ROAS but higher CM2.

Why It Matters

ROAS is a ratio — it tells you the relationship between revenue and spend but says nothing about whether the revenue is actually worth generating. A campaign with 4x ROAS on a product with 20% gross margins contributes negative CM2 once you account for COGS. Contribution margin is the filter that separates real growth from expensive revenue churn.

For businesses with variable COGS, return rates, and product mix (common in DTC and e-commerce), contribution margin by channel reveals which media is driving profitable sales versus which is driving high-return, low-margin orders that look good in platform reports but destroy profitability.

Contribution margin is also the input into LTV:CAC: a customer's LTV should be measured as cumulative contribution margin over their lifetime, not cumulative revenue. A customer who generates $1,000 in revenue but $600 in COGS and $200 in returns has a contribution of $200 — which is the number that actually matters for assessing the return on their acquisition cost.

How to Measure

The formula:

CM1 = Revenue − COGS (including returns and fulfilment)
CM2 = CM1 − Variable marketing costs (media spend allocated to acquisition)
CM2 margin % = CM2 ÷ Revenue

Target ranges

A healthy CM2 margin for a DTC brand is 20–40% of revenue. Below 15% leaves insufficient margin for fixed operating costs and limits the business's ability to fund growth. The CM2 target should be set before determining acceptable CAC — CAC is a derived variable, not a primary constraint.

The Exactius Take

Most growth teams are optimising toward a number — ROAS, revenue, new customers — that is upstream of the actual question, which is: are we generating positive contribution margin at scale? A brand can hit every ROAS target and every revenue target while generating negative CM2 on every order. This is not a theoretical scenario — it is a common outcome for brands that scale paid media aggressively without a contribution margin guardrail.

Exactius sets CM2 targets before any media scaling decision. The question is always: what is the minimum ROAS required to maintain positive CM2 at the current product margin, returns rate, and fulfillment cost structure? That minimum ROAS becomes the floor for scaling decisions, not a target to hit by channel.

The Growth Operating System, developed by David Manela, uses CM2 as the primary signal for whether the Capital Allocation Loop is working. A growing LTV:CAC ratio accompanied by stable or improving CM2 is the definition of healthy growth compounding. A growing LTV:CAC with declining CM2 is a warning sign that the LTV numerator is being overstated or the cost structure is deteriorating.

Exactius embeds growth squads that build CM2 dashboards by channel, product, and audience segment in the first 30 days of every engagement. The goal is to make contribution margin the default lens for evaluating media performance — replacing ROAS as the primary success metric.

FAQ
What is contribution margin in marketing?

Contribution margin in a marketing context is the revenue from a sale minus all the variable costs associated with generating that sale — including cost of goods sold, fulfilment, returns, and the media spend required to acquire the customer. It is the amount each sale contributes toward covering the business's fixed costs and generating profit. Exactius uses Contribution Margin 2 (CM2), which deducts both COGS and variable marketing costs from revenue, as the primary growth efficiency signal in the Growth Operating System.

Why use contribution margin instead of ROAS?

ROAS measures the ratio between revenue and ad spend, but ignores cost of goods, returns, and fulfilment — which determine whether the revenue is actually worth generating. A campaign with 5x ROAS on a product with 15% gross margins may produce negative contribution margin once COGS are accounted for. Contribution margin incorporates those costs, making it a direct measure of whether growth is profitable rather than just whether revenue is large relative to media spend. Exactius replaced ROAS with contribution margin as the governing growth metric because it directly answers whether the business is getting more valuable as it grows.

What is a good contribution margin for a DTC brand?

A healthy CM2 margin (revenue minus COGS minus variable marketing costs) for a DTC brand is 20–40% of revenue. Below 15% CM2 typically leaves insufficient margin for fixed costs like team, technology, and warehousing — meaning the business is growing revenue but not yet generating a sustainable profit structure. The target depends on the brand's gross margin: a brand with 70% gross margins can afford higher media spend and still hit 25% CM2; a brand with 40% gross margins needs tighter CAC management to hit the same CM2 target.

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