Last Click Attribution for Email: Why It’s Misleading and What to Use Instead
In this article, I’ll explore what last click attribution for email really means…
Last click attribution for email campaigns has long been the default model used by marketers and analytics platforms. It’s simple, accessible, and familiar. But in today’s multi-touch customer journeys, it often hides the true impact of your email marketing efforts.
In this article, I’ll explore:
- What last click attribution means in email marketing
- Its key limitations
- A smarter alternative: 2-day post-open attribution
- How to implement and compare both models
- Why modern marketers should evolve beyond last-click
✅ What Is Last Click Attribution for Email?
Last click attribution is a model that gives 100% of the credit for a conversion to the last channel the user clicked on before completing a purchase.
In email marketing, that means:
- If a user clicks an email and purchases immediately, the email gets full credit.
- If a user opens an email but doesn’t click, and later converts via another channel like paid search or direct, the email gets zero credit.
This model is commonly used in platforms like Google Analytics—but it severely underrepresents the impact of last click attribution for email.
⚠️ Why Last Click Attribution for Email Is Inaccurate
1. Email Opens Drive Intent, Even Without Clicks
Many users open emails, browse your site manually, or search for your brand later. Last-click attribution ignores that entirely unless there was a direct click.
2. Cross-Device and Cross-Session Behavior
Customers might open an email on their phone and purchase later on their desktop. Last-click models—especially session-based ones—completely miss this behavior.
3. Bias Toward Paid Channels
Email often rekindles interest. But if the final step is retargeting or branded search, those channels get 100% of the credit, making CRM seem less effective than it is.
4. Short-Term Thinking
A user who converts a few hours (or even one day) after opening your email is still influenced by it. Last-click fails to recognize these delayed, but logical, behaviors.
🧠 A Better Alternative: 2-Day Attribution After Email Open
To get a clearer view of email campaign impact, I recommend using a 2-day post-open attribution model.
🔍 What It Is
Any order placed within 48 hours of a user opening an email is attributed to that email—even if the last click was through another channel.
🎯 Why 48 Hours?
- It captures delayed conversions without going too far
- Accounts for decision-making time in e-commerce
- Reflects realistic customer behavior across sessions and devices
📊 Comparing Attribution Models: A Real Example
At the last company I worked at, we ran this comparison across several email campaigns. The difference was dramatic:
| Attribution Model | Attributed Orders | Revenue | Conversion Rate |
|---|---|---|---|
| Last Click (Email) | 147 | €4,370 | 0.5% |
| 2-Day Post-Open | 511 | €14,150 | 1.8% |
This showed a 248% increase in attributed orders just by using a more realistic time-based attribution model.
⚙️ How to Implement 2-Day Post-Open Attribution
1. Track Email Opens
Include a user ID and campaign ID in your email tracking. Example: ?source=email&campaign_id=xyz&user_id=abc
2. Store and Match Opens to Orders
You’ll need two key datasets:
- Email Opens: user_id, campaign_id, open_datetime
- Orders: user_id, order_datetime
3. SQL/Pseudocode Example
SELECT o.order_id, e.campaign_id
FROM orders o
JOIN email_opens e ON o.user_id = e.user_id
WHERE o.order_datetime BETWEEN e.open_datetime AND DATEADD(DAY, 2, e.open_datetime)
This simple query lets you tie back conversions to email activity within a 48-hour window.
📈 When to Use Each Attribution Model
| Model | Best For |
|---|---|
| Last Click Attribution | Quick promotions, direct-response emails |
| 2-Day Post-Open Attribution | Nurturing campaigns, CRM impact measurement, lifecycle flows |
| First Click Attribution | Awareness/brand campaigns |
| Multi-Touch Attribution | Full-funnel journey analysis |
🧩 Final Thoughts
Last click attribution for email is outdated. It simplifies reporting but fails to reflect real human behavior.
If your email campaigns are meant to build relationships, trigger exploration, or restart the purchase cycle, then relying solely on last click models will lead you to underinvest in one of your most powerful channels.
Switching to a 2-day post-open attribution model is simple, more accurate, and gives email the credit it actually deserves, especially when compared to last click attribution for email.
🔍 Keywords covered:
- last click attribution for email
- email attribution models
- email marketing ROI measurement
- post-open attribution
- CRM campaign performance
If you’re interested in a deeper walkthrough or a Power BI template to apply this model, feel free to reach out via my contact page.
📊 Curious how to implement a better attribution model using real data? Check out my in-depth walkthrough of post-click attribution using Emarsys Open Data, where I share a full BigQuery example and explain how to tie email clicks to purchases through session analysis.