Contribution Margin — how much is left after variable costs

Contribution Margin is the cash balance the business keeps from one specific sale after subtracting from the selling price all the accompanying variable costs — not the fixed ones.

The formula for calculating it is simple:

Contribution Margin = selling price − variable costs per unit A variable cost is whatever follows each new unit sold: the product cost (COGS), courier delivery, packaging, the specific ad spend, the per-order bonus. This amount goes toward covering the business's global fixed costs.

The typical founder mistake: subtracting only the product cost from the selling price and counting the rest as "profit," without accounting for the variable costs of ads, courier, and packaging. As a result, they set discounts and ad budgets as if they had far more margin than they really do — and at the end of the chain the margin slips below zero.

CoreFlow's reading: this is where the ad budget begins

Contribution Margin is the foundation for calculating Break-even ROAS. It's precisely what defines the real "advertising room" that marketing must fit within when acquiring a new customer, so the business doesn't run at a loss.

The logic is simple: if one sale leaves X lari after variable costs, then spending more than X lari to acquire that customer (CAC / CPA) is a direct loss — until LTV justifies it through repeat purchases. A founder who doesn't know their Contribution Margin is essentially setting ad budgets and discounts blind.

Hypothetical example (illustrative figures)

Say a product sells for ₾100. Variable costs: COGS = ₾45, courier = ₾8, packaging = ₾2.

Contribution Margin = 100 − (45 + 8 + 2) = ₾45.

This means spending more than ₾45 to acquire a new customer is a loss on a single purchase — and to cover fixed costs the business is left with only this ₾45 per sale, not the full ₾55.

The main danger: confusing total margin with the variable one

It's a serious mistake when a founder perceives Gross Margin (which only subtracts COGS) as the Contribution Margin and thinks they have more free money per sale. A sale's real "advertising room" always remains after the full sum of variable costs — and that's exactly what should be the starting point for budgeting, not the total margin.

Diagnostic question

Do you know exactly what your top product's Contribution Margin is in lari per sale — i.e., after subtracting COGS, courier, packaging, and ad spend — or do you set budget and discounts by the feel of the total margin? ---

FAQ (frequently asked questions)

Are Contribution Margin and Gross Margin the same thing?

No. Gross Margin subtracts only COGS. Contribution Margin subtracts every variable cost — courier, packaging, the per-order ads, and the bonus. For ad budgeting, the second figure is the starting point.

Why don't I subtract fixed costs?

Because a fixed cost (rent, salary) doesn't follow one sale — it exists anyway. Contribution Margin is precisely the money that accumulates to cover these fixed costs. See Break-even Point.

Related terms: Break-even ROAS · Gross Margin · COGS · Unit Economics

Reviewed by CoreFlow · Based on operational experience in Meta Ads, Messenger Sales, E-commerce, and retail growth in Georgia · Last reviewed: 2026-06-20