E-commerce Marketing — Which Channels to Use and How to Measure Them

Which e-commerce marketing channels should you use before you spend a single euro on advertising? In the EU, 73.56% of people aged 16 to 74 bought something online in the last 12 months — 77.82% among those who used the internet in that period — according to Eurostat's 2025 data (table isoc_ec_ib20, EU27, updated 17.04.2026). With that many buyers already shopping online, the real question for e-commerce marketing isn't whether to advertise, but which channel actually reaches people who are already looking for what you sell, and how to measure it once you do. This article maps the section: which channel answers which kind of search — Google, Meta, TikTok, price comparison sites, creators and your own SMS/email list — and how to measure every one of them with the same two numbers, ROAS and MER.

How shoppers find products online

Eurostat tracks how many people buy online, not which channel they used to find a specific product. There is no EU-wide ranking of search engines versus on-platform search, browsing, social media and AI tools — the kind of breakdown some national consumer surveys publish for their own market. What the EU data does show: among enterprises with 10 or more employees that sell online, 45.0% sell through an e-commerce marketplace, and 43.13% sell to buyers in other EU countries (Eurostat, table isoc_ec_esels, 2025) — marketplaces and cross-border reach are themselves a discovery channel, not just a sales channel.

Treat each paid channel below on its own evidence, rather than looking for one ranked list of "where shoppers search" — none is published at EU scale.

Paid channels: Google, Meta, TikTok, price comparison sites

Google. Product data reaches Google through a feed or structured data submitted in Merchant Center. Across most of the EU and several neighbouring markets, Shopping ads and free product listings must be placed through a Comparison Shopping Service (CSS) of the merchant's choice — Google's own Google Shopping is one of them, independent CSS partners are the others. Google's CSS country list names 21 countries: 18 EU member states and Norway, plus Switzerland and the UK (read 2026-10-02), so this isn't an EU-only requirement. The programme traces back to the European Commission's 27 June 2017 decision fining Google €2.42 billion for favouring its own comparison service in search results and ordering equal treatment for competing comparison services — an EU enforcement act, even though the CSS programme now also covers Switzerland, which was never party to it. Feed mechanics, Performance Max and setting a target ROAS are covered in the Google Shopping article.

Meta. Facebook and Instagram ads run on a product catalogue together with the Pixel and the Conversions API (read 2026-10-01). Meta's own November 2024 newsroom article about its subscription-for-no-ads product states the legal-basis change applies across "the EU, EEA and Switzerland" (read 2026-10-01) — not an EU-only mechanism. Meta announced the subscription on 30 October 2023 at €9.99/month on the web or €12.99 on iOS and Android, and on 12 November 2024 cut it to €5.99/€7.99 from the following day, alongside a new free "less personalised ads" option. The catalogue, Advantage+ shopping campaigns and dynamic remarketing are covered in the Meta Ads article.

TikTok. TikTok Shop, the seller programme, lists exactly 13 EU markets on its own seller centre (read 2026-10-01): Germany, Spain, Italy, Ireland, France, Poland, the Netherlands, Belgium, Czech Republic, Austria, Greece, Portugal and Hungary. TikTok Shop Ads, the paid version, runs on a narrower, separately published list: in Europe it covers only France, Ireland, Italy, Spain and the UK, with Germany added on TikTok's sales-objective page (both read 2026-10-02) — the other eight TikTok Shop markets are on neither list. Check both of TikTok's own lists for your country before budgeting for TikTok Shop Ads; the TikTok Shop article covers what each list does and doesn't include.

Price comparison sites. Comparison-shopping engines such as idealo and Kelkoo also work from your product feed, but fee models, click prices and country coverage vary by operator, and we found no single public rate card we could verify — so no click price is quoted here. Check the specific operator's own merchant terms for your market. When that kind of cost pays off is worked through in the article on price comparison sites.

Creators, affiliate marketing and reviews

Creator content, brand content and other buyers' reviews on social media all influence purchase decisions. How much each one contributes varies from study to study, and we found no EU-wide breakdown solid enough to quote — treat creator marketing as one real input among several, not a dominant channel.

That influence comes with disclosure obligations. The EU's Unfair Commercial Practices Directive (2005/29/EC, as amended by the Omnibus Directive 2019/2161) treats failing to disclose commercial intent as a misleading practice — and that includes paid or gifted content from creators and influencers. National regulators enforce it in their own way, but the disclosure duty itself is EU law. Since the Omnibus amendments, the same directive also bans submitting or commissioning fake consumer reviews, and claiming reviews come from genuine buyers without taking reasonable steps to check.

Affiliate marketing runs on the same disclosure logic, with a network in the middle. Awin, for one, runs country sites for many EU markets, from Germany, France, Italy and Spain to Poland and the Nordics (read 2026-10-02). Its headline numbers — 1 million publishers, 30,000 advertisers and £18 billion in revenue generated for advertisers in its last financial year — are global, not EU figures, so read them as a sense of scale only. Networks, influencer marketing and how to disclose a paid collaboration correctly are covered in the affiliate marketing article.

Owned channels: SMS and email

SMS and email follow the same legal rule. Under the EU's ePrivacy Directive (2002/58/EC), Article 13, direct marketing by "electronic mail" — which the directive defines broadly enough to include SMS — needs the recipient's prior consent. There is one exception, Article 13(2): if you obtained a customer's contact details in the course of a sale, you may market your own similar products or services to them, provided they were clearly given a free, easy way to object when the details were collected and in every message. That consent sits on top of, not instead of, the GDPR Article 6 basis you need to process their data in the first place. National transposition and enforcement differ by member state; the rule itself is EU-wide.

Email as a lifecycle channel — welcome sequences, reminders, segmentation — is covered in our email marketing article. SMS is usually priced per message, tiered by volume, by your gateway provider; there is no EU-wide price list worth quoting, so check your supplier's current rate card before budgeting a campaign. How to cost a campaign before you send it is covered in the article on SMS campaigns.

Measuring e-commerce marketing the same way across every channel

Measure every paid channel with the same formula: ROAS = conversion value ÷ ad spend. Google's own worked example (read 2026-10-01): $5 of sales value ÷ $1 of ad spend × 100% = 500% target ROAS — from June 2026, Google Ads shortened the strategy's name from "Maximize conversion value with a Target ROAS" to "Target ROAS," with no change to the mechanic. ROAS judges one ad, campaign or channel — not the whole business. That's what MER is for (marketing efficiency ratio, also called blended ROAS): total revenue ÷ total marketing spend (read 2026-10-01), calculated on store-wide numbers rather than inside any single ad platform's own panel.

Attribution decides which channel gets credit for a conversion when a buyer saw several. GA4 currently has three attribution models (read 2026-10-01): data-driven, "paid and organic last click," and "Google paid channels last click" — four older rule-based models (first click, linear, time decay, position-based) were retired in November 2023. Google Ads and Meta each report conversions by their own settings, so compare channels in one place — GA4, one attribution model — rather than trusting each platform's own number.

One European wrinkle in this measurement layer: since March 2024 Google has required consent signals for EEA traffic, under its EU user consent policy — which also covers end users in the UK and Switzerland (read 2026-10-02). Consent Mode is how a site passes those signals to Google. If your GA4 and Google Ads setup doesn't send them, the numbers can understate performance for European visitors. Measuring under consent, and how Consent Mode affects these numbers, is covered in the performance marketing article; the definitions of AOV, CAC and LTV you use to judge the return from these channels are in e-commerce KPIs.

If your measurement — GA4, server-side GTM, Meta Pixel and Conversions API — isn't configured correctly yet, we can help set it up and coordinate campaigns with a partner agency; we don't run Google or Meta campaigns ourselves.

Map of the section

Each of the nine articles in this section answers a different question about promoting a store — start with the one you have right now:

• Google Shopping — free product listings, Performance Max, and how to set a target ROAS.
• Performance marketing — ROAS, MER, GA4 attribution and measuring under consent.
• Meta Ads — product catalogue, Advantage+ shopping campaigns, dynamic remarketing, Pixel and Conversions API.
• TikTok Shop — which countries can sell through TikTok Shop, and which of them TikTok Shop Ads doesn't cover.
• Price comparison sites — how comparison engines bill you, and when the cost pays off.
• Affiliate marketing — affiliate networks, influencer marketing, and how to disclose a paid collaboration.
• SMS campaigns — the consent you need for the channel, message pricing, and email as a lifecycle channel.
• Selling online — whether you need to register a business, what DAC7 platform reporting means, and choosing between a marketplace and your own store.
• E-commerce statistics and trends — how many people buy online, and how to read figures that disagree between reports.

E-commerce marketing — where to start

Start with the order, not the budget. Product data and measurement come first — a feed in Google Merchant Center, a catalogue in Commerce Manager, the Pixel or Conversions API configured, GA4 set up for consent — and paid traffic second. Skip that order and every campaign ends up paying for clicks whose outcome you can't see in your own reports.

Then switch on what each channel offers for free. Free product listings in Google are on by default for new Merchant Center accounts and cost nothing before you add paid product ads. Raise the budget only once your analytics show where orders actually come from — and only in the channel that sells in your own data, not in a general industry statistic.