The Cost of Sale Will Not Always Look Like a Click

The cost of sale used to be discussed mainly through media spend, discounts and agency fees. Future commerce makes the cost picture wider. A sale may carry transaction fees, commission, integration cost, operational maintenance, fulfilment expectations, returns exposure and margin leakage through cannibalisation.

Why this matters now

This matters because a channel can grow revenue while weakening contribution. Marketplace growth may look useful until fees, advertising, returns and direct-channel cannibalisation are included. Agentic checkout may reduce friction but introduce new payment, platform or integration costs. Affiliate activity may support discovery or simply tax demand that already existed.

Retailers need a clearer contribution view before they decide which new surfaces are worth pursuing.

What is actually changing

The commercial model is moving from click cost to total route-to-sale cost. Media remains important, but it is only one line. Payment processing, platform commission, product content production, technical maintenance, feed management, customer service, delivery promises and returns all affect whether the sale is worth having.

Margin-aware trading becomes more important. A low-margin product sold through a high-fee surface may be poor business even if revenue rises.

What is often misunderstood

The misunderstanding is that every new route to sale is incremental. Some will be. Some will shift existing demand into a more expensive path. Some will create customers worth keeping. Others will create one-off, low-margin orders.

Another misunderstanding is that finance can solve this alone. Ecommerce, marketing, merchandising and operations need to agree how cost and value are measured.

What retailers should review

• What is the full contribution after fees, discount, fulfilment and returns?
• Which channels or surfaces cannibalise direct demand?
• Which products can afford commission or platform costs?
• Where do content, integration and maintenance costs sit?
• Are customer quality and repeat purchase included in the decision?

What good looks like

Good looks like route-to-sale economics by product group and customer type. The business knows which products should be pushed direct, which suit marketplaces, which can carry paid media cost and which should be protected from expensive acquisition.

It also knows when a higher first-order cost is acceptable because the customer repeats.

What not to overdo

Do not block every new route because the cost model is imperfect. Do not assume all external channels are bad. Do not make decisions from blended ROAS or gross revenue alone.

Use directional contribution to avoid obviously poor commercial choices.

Practical next step

Pick three routes to sale: direct site, marketplace and paid product listing. Compare gross revenue, margin, discount, fees, fulfilment, returns, media cost and repeat purchase. The result will usually change the channel conversation.