Definition

Behavioural email targeting sends messages triggered by specific subscriber actions or inactions on your website, app, or product. Unlike batch-and-blast campaigns sent to entire lists on a fixed schedule, behavioural emails are event-driven — they fire when a subscriber performs (or fails to perform) a defined action. Common triggers include page views (especially on high-intent pages like pricing), content downloads, product purchases, login frequency changes, feature adoption, and cart abandonment. These emails consistently outperform broadcast campaigns, with transaction rates 3-6 times higher according to industry benchmarks.

The effectiveness of behavioural targeting depends on the recency window — how long after the trigger event the email is sent. A cart abandonment email sent within 1 hour converts at approximately 10-15%, but waiting 24 hours drops that rate to under 5%. The conversion decay curve varies by trigger type: immediate-trigger events (abandoned cart, browse abandonment) require sub-hour send latency, while milestone triggers (post-purchase, onboarding) can tolerate 24-48 hour delays without significant performance loss.

Cooldown periods prevent over-sending when a subscriber repeatedly triggers the same event. Without cooldowns, a subscriber browsing multiple product pages could receive a separate email for each page view, resulting in send fatigue and unsubscribe spikes. Typical cooldown configurations suppress repeat triggers for 7-30 days depending on the trigger type. Cart abandonment emails typically have a 24-hour cooldown, browse abandonment emails have a 7-14 day cooldown, and login-triggered emails have a 30-day cooldown.

Best Practices

Define trigger events based on intent level, not just action type. A pricing page view signals higher purchase intent than a blog post view. Page views on "contact sales," "pricing," or "demo request" pages warrant faster and more direct triggers than content page views. Assign intent scores to each page type and use thresholds to determine when a trigger fires.

Set recency windows based on conversion decay curves for each trigger type. Run an A/B test sending the same behavioural email at 1 hour, 6 hours, 12 hours, 24 hours, and 48 hours post-trigger. Use the results to identify the optimal send window. For most e-commerce triggers, the first 60 minutes capture 40-50% of all conversions from that trigger.

Implement event deduplication and aggregation to prevent trigger overload. If a subscriber views three product pages in one session, aggregate those into a single email showing all three products rather than sending three separate emails. Deduplication logic should reset the cooldown timer on each new trigger event to ensure the most recent context is captured.

Build behavioural profiles that accumulate over time, not just single-event triggers. A subscriber who has viewed pricing three times in the last month, downloaded a whitepaper, and attended a webinar has a qualitatively different profile than someone who performed one of those actions once. Use cumulative behavioural scoring to trigger lifecycle stage transitions.

Test trigger latency carefully by comparing real-time sends against batched sends. Real-time sends (within 1-5 minutes) capture the highest conversion intent but increase infrastructure costs. For non-critical triggers like content recommendations, batching sends every 30-60 minutes reduces costs with minimal conversion impact (typically under 5% conversion loss).

How long should I wait after a trigger event to send?

For high-intent actions like cart abandonment, send within 1 hour — ideally within 15 minutes. For lower-intent signals like content page views, 24 hours is acceptable. Test the latency curve for each specific trigger type to find the optimal balance between responsiveness and conversion rate.

What is a cooldown period and why does it matter?

A cooldown period prevents sending multiple triggered emails for the same event type within a defined timeframe. Without cooldowns, a subscriber could receive a "we noticed you left items in your cart" email every time they leave a page. Typical cooldowns range from 24 hours (cart abandonment) to 30 days (login frequency changes).

How do I track custom events for behavioural triggering?

Implement event tracking using your ESP's SDK or API, or use a customer data platform (CDP) that pushes events to your ESP. Define a unified event schema with subscriber ID, event name, event properties, and timestamp. Ensure events fire client-side and server-side for reliability.

Do behavioural emails always outperform broadcast campaigns?

Yes, consistently. Behavioural emails achieve 3-6 times higher transaction rates than broadcast campaigns. The personalisation and relevance of event-driven messaging means subscribers receive emails that directly relate to their demonstrated interests, driving significantly higher engagement.

How many behavioural triggers should I have?

Start with 5-10 core behavioural triggers and expand once each is optimised. Typical high-impact triggers include welcome series, cart abandonment, browse abandonment, post-purchase follow-up, content download follow-up, feature adoption, win-back (inactive), milestone anniversary, and price drop alerts.