First-Touch vs Last-Touch Attribution
When a lead fills out your contact form, which marketing channel gets the credit?
If they first found you through a Google search three weeks ago, then came back via a Facebook ad last week, and finally typed your URL directly today, which channel “generated” that lead?
That’s the attribution question. And the answer depends on which model you use.
First-Touch Attribution
First-touch attribution gives all the credit to the channel that introduced the lead to your business. Whatever brought them in for the very first time, that’s the channel that gets credited.
Example: A visitor finds your site through organic search on Monday. They come back via a Google Ad on Wednesday. They submit your contact form on Friday after typing your URL directly. First-touch attribution credits Organic Search.
When it’s useful:
- Understanding which channels drive awareness and discovery
- Evaluating top-of-funnel marketing (content, SEO, social media)
- Reporting to clients on “where new leads are coming from”
When it falls short:
- Ignores everything that happened between discovery and conversion
- Over-credits channels that drive traffic but don’t drive action
- A visitor might have found you through search but only converted because of a retargeting ad
Last-Touch Attribution
Last-touch attribution gives all the credit to the channel that was active on the conversion visit, the visit where the lead actually filled out the form.
Example: Same scenario as above. Last-touch attribution credits Direct (because the visitor typed the URL directly on the day they submitted the form).
When it’s useful:
- Understanding which channels drive conversions
- Evaluating bottom-of-funnel marketing (retargeting, email nurture)
- Optimising campaigns for lead generation, not just traffic
When it falls short:
- Ignores the channels that built awareness and trust beforehand
- Over-credits “Direct” and “Email” (channels people use when they’ve already decided)
- Makes it look like top-of-funnel marketing doesn’t work
Why You Want Both
Neither model tells the full story on its own. First-touch tells you what’s filling your funnel. Last-touch tells you what’s converting it. Together, they give you a practical picture of your marketing.
| Scenario | First-Touch Says | Last-Touch Says | What Actually Happened |
|---|---|---|---|
| SEO → Retargeting ad → Form submit | Organic Search works! | Paid Search works! | SEO built awareness, ads closed the deal |
| Facebook ad → Direct visit → Form submit | Paid Social works! | Direct works! | The ad planted the seed, they came back when ready |
| Email → Email → Email → Form submit | Email works! | Email works! | Both agree: email is driving this lead |
When first-touch and last-touch agree, you can be confident in the attribution. When they disagree, you know there’s a multi-touch journey happening, and both channels deserve some credit.
What About Multi-Touch Attribution?
Multi-touch attribution (MTA) distributes credit across all touchpoints in a lead’s journey. It’s theoretically the most accurate model, but in practice:
- It requires tracking every single visit (multiple cookies, potentially server-side storage)
- It needs a model to decide how to split credit (linear, time-decay, position-based, algorithmic)
- It’s complex to implement and even harder to explain to clients
For most businesses, especially those doing lead generation rather than e-commerce, first-touch + last-touch is the practical sweet spot. You get 80% of the insight with 20% of the complexity.
How SourceTag Handles This
SourceTag captures both first-touch and last-touch attribution data in every form submission. When a visitor first arrives, both values are set to the same thing. As they return through different channels, the last-touch updates while the first-touch stays locked.
Your form submissions include fields like:
ft_channel: First-touch channel (e.g. “Organic Search”)ft_source: First-touch source (e.g. “google”)lt_channel: Last-touch channel (e.g. “Paid Search”)lt_source: Last-touch source (e.g. “google”)
Both flow into your CRM alongside the lead’s contact details, so you can report on either model, or both.