Definition
Last-touch attribution is a conversion credit model that assigns 100% of a conversion to the last email campaign the subscriber interacted with before taking the desired action — whether that interaction was an open, click or direct visit. If a subscriber received a welcome email, a newsletter and a promotional offer before purchasing, only the promotional offer would receive attribution credit under this model.
While last-touch is the default in most email platforms and the easiest to implement, it ignores earlier campaigns that may have built awareness, trust and purchase intent. It tends to overvalue lower-funnel, discount-driven campaigns and undervalue brand-building and educational emails.
When Last-Touch Makes Sense
- When you need a simple, standardised attribution model that works across channels
- For transactional or triggered campaigns where intent is immediate
- When campaign timelines are short and subscribers typically convert from a single touchpoint
Limitations
- It provides no visibility into the contribution of earlier nurturing or educational emails
- It can incentivise aggressive promotional tactics at the expense of relationship building
- It creates misleading ROI comparisons between upper-funnel content and lower-funnel offers
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.
ARPU (Average Revenue Per User)
ARPU (Average Revenue Per User) is a metric that measures the average revenue generated per email subscriber over a specific period, used to evaluate list value and campaign effectiveness.
Attention Rate
Attention rate is the percentage of email opens that last longer than 5 seconds, distinguishing genuine reads from passive opens, preview-pane views, or Apple MPP auto-loads.
Bounce Rate
Email bounce rate is the percentage of emails that were rejected by the receiving server before reaching the recipient. It is a key indicator of list health and data quality.
Campaign Internal Rate of Return (IRR)
Campaign IRR is the annualised return rate earned by an email campaign, accounting for the timing and magnitude of costs and revenue across the campaign's full lifecycle.
Campaign Lifted Revenue
Campaign lifted revenue is the additional revenue generated by an email campaign beyond what would have occurred without it, measured via a holdout group or statistical lift analysis.