First-Touch vs Last-Touch Attribution: Which One Should You Use?
First-touch vs last-touch attribution
When a lead fills out your contact form, which marketing channel gets the credit? If they found you through a Google search three weeks ago, came back via a Facebook ad last week, and typed your URL in directly today, 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 the very first time.
Example: a visitor finds your site through organic search on Monday, comes back via a Google ad on Wednesday, and submits your contact form on Friday after typing your URL directly. First-touch attribution credits Organic Search.
It’s useful for understanding which channels drive awareness and discovery, for evaluating top-of-funnel marketing like content, SEO and social media, and for reporting to clients on where new leads are coming from. Its blind spot is everything that happened between discovery and conversion, so it 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, and first-touch alone won’t tell you that ad ever ran.
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. In the same scenario above, last-touch credits Direct, because the visitor typed the URL directly on the day they submitted the form.
This model tells you which channels are driving conversions right now, which makes it useful for bottom-of-funnel work like retargeting and email nurture. But it has the opposite problem to first-touch: it ignores the channels that built awareness and trust beforehand, over-credits Direct and Email (the channels people use once they’ve already decided), and can make it look like your top-of-funnel marketing isn’t doing anything.
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 workable picture of your marketing.
| Scenario | First-touch says | Last-touch says | What actually happened |
|---|---|---|---|
| SEO → Retargeting ad → Form submit | Organic Search | Display | SEO built awareness, ads closed the deal |
| Facebook ad → Direct visit → Form submit | Paid Social | Direct | The ad planted the seed, they came back when ready |
| Email → Email → Email → Form submit | Both agree: email is driving this lead |
When first-touch and last-touch agree, you can trust the attribution. When they disagree, there’s a multi-touch story happening and both channels deserve some credit.
Multi-touch attribution
Multi-touch attribution (MTA) spreads credit across every touchpoint in a lead’s path to conversion. It’s the most theoretically accurate model, but it requires tracking every single visit, it needs some formula to decide how to split the credit (linear, time-decay, position-based, algorithmic), and it’s complicated enough to build that it’s harder still to explain to a client.
For most businesses, especially those doing lead generation rather than e-commerce, first-touch plus last-touch is the practical middle ground. You get most of the insight without the modelling exercise.
How SourceTag handles this
SourceTag captures both first-touch and last-touch attribution on every form submission. When a visitor first arrives, both values are set to the same thing. As they return through different channels, last-touch updates while first-touch stays locked.
Your form submissions include fields like:
st_fc_channel: first-click channel (e.g. “Organic Search”)st_fc_detail_1: first-click source/platform (e.g. “google”)st_lc_channel: last-click channel (e.g. “Paid Search”)st_lc_detail_1: last-click source/platform (e.g. “google”)
Both flow into your CRM alongside the lead’s contact details, so you can report on either model, or both.