Definition
Personalisation and customisation are two approaches to tailoring email content to individual subscribers. Personalisation is system-driven — the email platform automatically adjusts content based on subscriber data. Customisation is subscriber-driven — the subscriber chooses preferences, topics, and settings that affect the content they receive.
Both approaches improve engagement, but they work through different mechanisms and are appropriate in different contexts.
Personalisation vs Customisation
| Factor | Personalisation | Customisation |
|---|---|---|
| Who controls the content | The system (automated) | The subscriber (manual) |
| Data source | Behavioural, transactional data | Self-reported preferences |
| Example | "You might also like..." based on past purchases | "Select your topics of interest" in preference centre |
| Setup effort | Moderate (requires data integration) | Low (preference centre setup) |
| Scalability | Highly scalable (automated) | Moderate (requires subscriber action) |
When to Use Each
| Scenario | Best Approach | Why |
|---|---|---|
| Product recommendations | Personalisation | Based on behaviour, not self-report |
| Email frequency | Customisation | Subscriber sets their own cadence |
| Content topics | Both | Use personalisation initially, offer customisation as preference |
| Send time | Personalisation | Algorithm optimises based on behaviour |
| Email format | Customisation | Subscriber chooses HTML or plain text |
Combining Personalisation and Customisation
The most effective email programmes combine both:
- Use personalisation for dynamic content — product recommendations, behaviour-based offers, send time optimisation.
- Use customisation for preference-based settings — topic selection, frequency choice, format preference.
- Allow subscribers to override personalisation with customisation — a subscriber who customises their topics should stop receiving personalised recommendations outside those topics.
Average Benchmarks
| Approach | Open Rate Impact | Click Rate Impact |
|---|---|---|
| No personalisation or customisation | Baseline | Baseline |
| Basic personalisation (name only) | +5-10% | +2-5% |
| Behavioural personalisation | +15-30% | +10-25% |
| Subscriber customisation (preferences) | +10-20% | +8-15% |
| Combined approach | +20-40% | +15-30% |
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Related Glossary Terms
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Account-Based Marketing Email
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AI Email Summary
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AI Inbox Summary
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AI Inbox
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Frequently Asked Questions
Behavioural personalisation generally produces higher engagement because it requires no effort from the subscriber. However, customisation gives subscribers control over their experience, which increases satisfaction and reduces unsubscribes.
Yes. Personalisation that reveals too much knowledge about the subscriber can feel creepy. "We noticed you looked at this product 5 times" is less effective than "Customers who viewed this also bought." Balance personalisation depth with privacy comfort.
A preference centre is the primary tool for customisation. Allow subscribers to select topics, frequency, format, and content types. Link to the preference centre in every email footer and in your welcome sequence.
Customisation can override personalisation if a subscribers stated preferences do not match their behaviour. The best approach uses personalisation by default and allows subscribers to customise as a refinement.
Behavioural product recommendations based on past purchases or browsing history are the most effective personalisation technique, generating 30-60% higher click rates than non-personalised alternatives.