Definition
Segmentation and personalisation are two complementary techniques for making email more relevant to subscribers. Segmentation determines which subscribers receive which emails by dividing the list into groups. Personalisation determines how the email content is tailored within those groups.
Think of segmentation as deciding who to send to, and personalisation as deciding what to send them. Segmentation is broader, personalisation is deeper.
Segmentation vs Personalisation
| Factor | Segmentation | Personalisation |
|---|---|---|
| Level | List level — divides subscribers into groups | Individual level — tailors content per person |
| Question answered | "Who should receive this email?" | "What should each recipient see?" |
| Implementation | Tags, lists, segments, filters | Merge tags, dynamic content blocks |
| Example | "Send this offer to customers who purchased in the last 30 days" | "Show the customers name in the greeting and their last purchase in the body" |
How They Work Together
Segmentation and personalisation are most effective when combined:
| Segmentation Layer | Personalisation Layer | Result |
|---|---|---|
| Segment: Recent purchasers | Personalise: Product recommendations based on purchase | High relevance |
| Segment: Inactive subscribers | Personalise: Win-back offer based on last purchase | Targeted re-engagement |
| Segment: Topic preferences | Personalise: Content matching selected topics | Consistent relevance |
Average Benchmarks
| Approach | Engagement Impact |
|---|---|
| No segmentation or personalisation | Baseline |
| Segmentation only | +20-40% |
| Personalisation only | +15-30% |
| Segmentation + personalisation | +40-80% |
Common Mistakes
- Confusing the two: Using segmentation when personalisation would be more effective, or vice versa.
- Segmentation without personalisation: Sending different content to different segments is effective, but personalising within each segment multiplies the impact.
- Personalisation without segmentation: Personalising content for the wrong audience wastes the personalisation effort.
- Over-segmentation: Creating too many segments that cannot be supported with distinct content.
- Under-personalisation: Using only first name personalisation when behavioural data supports deeper personalisation.
Related Glossary Terms
A/B Testing
A/B testing in email marketing is the practice of sending two variations of an email to a small sample of your list to determine which version performs better before sending the winner to the remaining subscribers.
Abandoned Cart Email
An abandoned cart email is an automated message sent to customers who added items to their online shopping cart but left without completing the purchase. It is one of the highest-converting email types in ecommerce.
AIDA Model for Email
The AIDA model (Attention, Interest, Desire, Action) is a classic copywriting framework used to structure email campaigns that guide subscribers from awareness to conversion.
AMP for Email
AMP for Email is a Google-developed framework that allows email messages to include interactive elements like forms, carousels, accordions, and live content. It turns static emails into dynamic, interactive experiences directly inside the inbox.
Anchoring Effect in Email Marketing
The anchoring effect is a cognitive bias where the first piece of information presented (the anchor) influences subsequent decisions, used in email to frame pricing and value perception.
Announcement Email
An announcement email is a dedicated campaign that communicates a specific update, milestone, or change to subscribers, from product launches and feature releases to company news and events.
Frequently Asked Questions
Start with segmentation. It delivers faster results with less technical complexity. Basic segmentation by engagement level or signup source typically improves engagement by 20-40%. Add personalisation after segmentation is working.
Segmentation works at any list size. Even a list of 100 subscribers can be segmented by signup source or expressed interest. Personalisation requires sufficient data per segment to generate meaningful content variations.
Yes. Most ESPs support automated segmentation rules and dynamic content personalisation. Automated segments update as subscriber behaviour changes. Personalisation is applied automatically based on subscriber profile data.
Segment when different groups of subscribers need fundamentally different content (different offers, different products). Personalise when all subscribers receive the same email but the content within should vary (recommendations, images, details).
Behavioural segmentation (past purchase category) combined with behavioural personalisation (products from that category) produces the highest engagement lift, typically 50-100% improvement over non-targeted campaigns.