Making sense of paid media with cost-per-sale marketing

Traditionally, paid media was seen as the primary mechanism for e-commerce growth. Investing budget into online channels with established audiences consistently drove traffic to retailers, while attribution efforts allowed them to get a sense of return on advertising spending (ROAS). 

 

There were drawbacks, of course. Each channel, whether Google ads, banner, social or influencer, has different ways of attribution and of tracking traffic. Every new platform required new skills, which meant investing in talent that was often in short supply.

 

 

Changing customer journeys, higher costs

Plus, while there are ways to track customer journeys, customers today make thorough decisions ahead of any purchase, even on low-value items. The customer journey now starts with research - checking prices ahead of going into the store to try items, before half-heartedly making a purchase. With the Consumer Contracts Regulation 2013 (originally the Distance Selling Act) protecting customers with free refunds and returns, this can often result in a change of mind, leading to product returns.

 

Trying to keep up with the customer buying journey and tying it to one specific point of purchase or sales route is a full-time job itself, never mind working out whether a specific advertising or marketing tactic actually helped convert into a sale.

 

These quirks, to put them politely, were fine while costs remained low, and fewer businesses sold online. That’s not the case anymore, with competition for customers growing. Analysis suggests there are more than three million e-commerce sites in Europe, not including the international giants such as Amazon, Temu, Shein or the recent European launch of JD’s JoyBuy online marketplace.

 

While there are more people buying online (from 62% of consumers in the EU, to 78% in 2025), it’s costing more to get in front of those audiences. Average e-commerce customer acquisition costs have grown significantly over the last five years; depending on the vertical, anywhere between 40-60%. From a paid media perspective, the average cost-per-click (CPC) on Google rose to $5.26 in 2025, a 12.9% year-over-year increase, with 87% of industries seeing CPC increases.

 

When you think that the average profit margin for an e-commerce business usually falls between 10-20% net profit (which is what you get once you take into account product costs, fulfilment, shipping, processing and platform fees and ad spend), that sort of increase is going to hit hard for any business. Particularly when there are limited guarantees on what paid media is actually delivering.

 

 

Is this affiliate marketing’s moment?

One type of paid channel that offers a slightly different approach is affiliate marketing. Affiliates are individuals or organisations that promote business products or services in exchange for a commission when specific actions, like sales or sign-ups, are completed.

 

Affiliate marketing’s pitch to retailers is fairly straightforward: the traffic has already expressed interest in the product or service by engaging with the affiliate’s content (a price comparison website link/recommendation or an influencer recommending on their socials etc). The retailer gets access to the affiliate’s engaged audience, and the affiliate gets paid for driving traffic that converts into sales.

 

It all makes sense on paper, but it still requires work. Questions remain on certain affiliate platforms about transparency and attribution (which can cause confusion for both brands and affiliates). From a retailer perspective, there is also the need to commit dedicated resources to manage the different channels within affiliate marketing, from the major platforms like Amazon and Rakuten, to social programmes such as TikTok and Meta, and then the grey area of where influencers sit.

 

So that leaves online retailers with a paid media programme that’s hammering margins, and an alternative that’s not quite clicking into gear.

 

 

Champion sales over traffic

There are all sorts of solutions out there that will promise to solve all these problems. Digital commerce has seen AI services springing up that can analyse the entire journey, not just where the last click was. These could, to be fair, genuinely make a difference, but before retailers rush to invest in another new technology, they need to invest in a mindset shift.

 

Historically, a cost-per-click (CPC) approach, where you paid for traffic, meant being grateful for what you could get. Success should absolutely be rewarded, but really what success looks like needs to be reconsidered. Can you pay salaries, suppliers, taxes, warehousing, and all the other costs of running a business with clicks and views? No, you pay them with cash, and so that should be the metric.

 

Therefore, the focus should be on how much cash is coming into the business. What’s attracting those buying customers? Which sales tactic or channels are they coming to you from? Once businesses have established that, then that’s where the money should be invested - back into those areas that work and rewarding them for clear results.

 

This is a focus on cost-per-sale (CPS), where traffic is only paid for when it delivers a direct, attributable sale.

 

 

A transparent, sales-driving future

Once you’re in that CPS mindset, then you’ve got a better idea of what you need to track and how you attribute sales, and what technology you should be using: tools that are geared towards CPS over CPC, and that prioritise transparency for both brands and retailers.

 

E-commerce is going to continue to grow, which only means more competition. Paid media’s position as the main way to capture traffic means it’ll be able to charge a premium for that access, adding to that pressure on margins. To protect them, brands and retailers need to rethink how they pay for traffic. Switching to a CPS model makes sure that they’re only paying for traffic that genuinely converts, protecting budget and allowing retailers to focus on the channels that will help them expand. 

 

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Manus Ó Dálaigh is Country Manager at Business League

 

Main image courtesy of iStockPhoto.com and MicroStockHub