The essentials
- Definition: segmenting means dividing your audience into homogeneous groups in order to adapt the message, the offer, the channel and the frequency to each one, instead of a single message for everyone.
- 2026 results: a segmented email gets 30 to 60% more clicks than a blanket send; advertising by intent segment cuts the cost per conversion by 20 to 40%.
- Four families: who (profile, company), what (behaviour, purchases), where (channel, location), when (journey stage, recency).
- The rule: three to six segments per channel, each with at least 500 to 1,000 people in advertising, with a different message; beyond that, nobody follows them any more.
Segmentation means dividing your audience into homogeneous groups according to shared criteria, so that each one receives the message, the offer, the channel and the frequency that suit it. Rather than a generic message sent to everyone, it produces campaigns that are more relevant and less expensive: in 2026, a segmented email gets 30 to 60% more clicks than a blanket send, and an advertising campaign built on intent segments cuts the cost per conversion by 20 to 40%. This article gives the criteria, the useful segments by channel, the minimum size, the tools and the mistakes. Segmentation specific to social advertising is covered in detail in audience segmentation in SMA.
The four families of criteria
| Family | Criteria | Source | Main use |
|---|---|---|---|
| Who (profile) | B2C: age, situation, location; B2B: sector, size, job role, revenue | CRM, forms, LinkedIn, declared data | Message and offer |
| What (behaviour) | Pages viewed, products browsed, purchases, frequency, basket, content read, emails clicked | GA4, e-commerce platform, emailing tool | Recommendation, follow-up, retention |
| Where (channel and place) | Acquisition source, device, geographic area, point of sale | GA4, UTM, CRM | Channel choice, local message |
| When (journey) | Stage (discovery, consideration, decision, customer, inactive), recency, tenure | CRM, GA4, emailing | Sequences, contact pressure, reactivation |
The most profitable segments cross two families: a behaviour and a stage (“viewed the pricing page, not yet a customer”), a profile and a behaviour (“industrial SME, downloaded the guide”). A segment defined by a single profile criterion (“women aged 25 to 34”) says little about intent.
The segments that pay off, by channel
Website and personalisation
- New visitors and known visitors: different welcome, proof and navigation.
- Acquisition source: a visitor coming from an advert about a specific offer sees that offer first.
- Location: local content, prices and contacts.
- Logged-in customers: history, recommendations, repeat orders.
Email and CRM
- Journey stage: prospect, qualified lead, customer, customer inactive for 6 months; one sequence per stage.
- Engagement: clickers over the last 90 days, openers without a click, inactives; frequency adapted, reactivation then cleaning.
- Purchase behaviour: category, average basket, frequency; recommendations and targeted offers.
- B2B profile: sector and job role; case studies and arguments to match.
Advertising (Google, Meta, LinkedIn)
- Intent: visitors to pricing and quote pages, abandoned baskets, content readers; message and bid by level of intent; see remarketing.
- Customers: excluded from acquisition, targeted for repeat purchase or upselling.
- Lookalike audiences: built from your best customers, not from all your visitors; see lookalike audiences.
- B2B profile on LinkedIn: job role, sector, size, with content for each segment.
Behavioural audiences are built in GA4 and shared with Google Ads; the procedure is in creating a custom audience in GA4. On the Google Ads side, the options are covered in detail in Google Ads custom segments.
How many segments, and how big?
| Channel | Recommended number of segments | Minimum size per segment | Why |
|---|---|---|---|
| Meta, TikTok advertising | 3 to 5 | 1,000 active people (10,000 for acquisition) | Below this threshold, delivery does not stabilise and the CPM rises |
| Google Ads (audiences) | 3 to 5 | 1,000 on search, 100 on display | Thresholds imposed by Google |
| LinkedIn Ads | 2 to 4 | 300 (LinkedIn minimum), 5,000 recommended | High cost per thousand, narrow audiences |
| 4 to 8 | 200 to 500 contacts | To read a click-through rate with a minimum of reliability | |
| Website (personalisation) | 2 to 4 | 10% of traffic | Content effort per segment |
More segments is not better: each segment calls for a message, tracking and a budget. Three to six clearly distinct segments, with readable results, are worth more than twenty micro-segments whose performance nobody reads. A segment is justified if it receives a different message and if its performance is compared with the others.
Setting up segmentation
- Start from the decisions: which message, which offer or which frequency would change from one group to another? If nothing changes, the segment is pointless.
- Check the data: the criteria you choose must be available and reliable (CRM fields filled in, GA4 events configured, consent obtained).
- Create the segments in the tools: GA4 audiences, lists and fields in the emailing tool, audiences in the advertising platforms, with a shared naming convention.
- Adapt the message per segment: a different piece of proof, offer or tone; segmentation without an adapted message produces nothing.
- Measure per segment: click-through rate, cost per conversion, revenue, compared between segments and with the blanket send; merge the segments that behave the same way.
- Review quarterly: segments age; a 2024 customer who has been inactive since is no longer a customer.
The frequent mistakes
- Segmenting by profile alone: age or sector without behaviour or stage is a poor predictor of intent.
- Segments that are too small: unstable delivery in advertising, unreadable statistics in email.
- The same message everywhere: segments created in the tool, a single piece of content sent.
- Forgetting exclusions: customers receive acquisition advertising, applicants receive sales offers.
- Ignoring consent: advertising segments only contain visitors who have consented (25 to 40% refusal in France); email segments require explicit consent.
- Not measuring: without a comparison between segments, there is no way to know whether segmentation pays off.
How GreenRed helps
Rather than juggling several tools, GreenRed's SMO and SMA social media tracking brings these metrics together in a single dashboard, compares them over time and tells you which actions come first. You can try it free, with no card, from the Pricing.
Frequently asked questions
What is audience segmentation in digital marketing?
Dividing your audience into homogeneous groups according to shared criteria (profile, behaviour, channel, journey stage), in order to adapt the message, the offer, the channel and the frequency to each group. It applies to the website, email, the CRM and advertising.
Which segmentation criteria are the most effective?
Crossings of a behaviour and a journey stage (“viewed the pricing page, not yet a customer”, “customer inactive for 6 months”) or of a profile and a behaviour. A profile criterion on its own (age, sector) is a poor predictor of intent and produces segments that pay off little.
How many segments should you create?
Three to five per advertising channel, four to eight in email, two to four for website personalisation. Each segment must receive a different message and be big enough for a reliable reading: 1,000 active people in social advertising, 200 to 500 contacts in email.
What results can you expect from segmentation?
In 2026, a segmented email gets 30 to 60% more clicks than a blanket send, and advertising by intent segment cuts the cost per conversion by 20 to 40%. The gain comes from the adapted message and the exclusions, not from simply creating the segments in the tool.
Where should you start?
With the journey stage: prospect, qualified lead, customer, inactive, applied to email (one sequence per stage) and to advertising exclusions (customers are taken out of acquisition). This split is set up in a week and produces most of the gain; the other axes are added afterwards.