Skip to main content

Tracking campaign sources with UTM parameters

See which ad, newsletter or post brought each supporter: CamBuildr records UTM parameters on every landing page interaction and lets you filter target audiences by them.

Written by Domonkos Horváth

When you promote a landing page through ads, newsletters or social posts, you want to know which channel actually brought each supporter. CamBuildr records the UTM parameters of every visit and attaches them to everything a person does — so you can see, filter and automate by acquisition source.

What are UTM parameters?

UTM parameters are small tags you add to the links you share. CamBuildr understands the five standard ones:

  • utm_source – where the traffic comes from (e.g. google, facebook, newsletter)

  • utm_medium – the channel type (e.g. cpc, email, social)

  • utm_campaign – the campaign name (e.g. spring-appeal)

  • utm_term – optional keyword or targeting detail

  • utm_content – optional variant, e.g. to tell two ad creatives apart

A tagged link looks like this: https://your-page.org/petition?utm_source=facebook&utm_medium=social&utm_campaign=spring-appeal

In addition to the five UTM parameters, CamBuildr also records the ad click IDs that advertising platforms append to their links automatically:

  • fbclid – Meta (Facebook/Instagram) click ID

  • gclid – Google Ads click ID

  • li_fat_id – LinkedIn ads click ID

Click IDs are opaque per-click tokens, so they are stored with each interaction for reference (e.g. for exports or webhook integrations) but are not shown in the interface and cannot be used in filters — use the UTM parameters for that.

How CamBuildr captures them

There is nothing to configure. When a visitor opens a landing page through a tagged link, CamBuildr remembers the parameters for that browser session and attaches them to whatever the visitor does next:

  • signing up through a form

  • donating or purchasing (the attribution is kept even though the payment confirmation arrives later)

  • answering a survey

  • voting or submitting content

Because the parameters are remembered for the session, the attribution survives multi-step flows — a supporter who reads the page first and donates a few minutes later is still credited to the original ad. Double-opt-in confirmations keep the attribution as well.

Where you see them

On a person's profile you'll find a Marketing attribution card showing two touchpoints:

  • First touch – the parameters of the very first tracked interaction. This answers "which channel won this supporter?"

  • Last touch – the parameters of the most recent tracked interaction. This answers "which channel re-activated them most recently?"

Each entry in the person's activity timeline also shows the parameters that were recorded with that specific action, so you can trace every single signup, donation or survey answer back to its source.

Filtering target audiences by source

In the target audience builder you'll find the UTM Attribution filter in the Landing page activity category. Pick:

  1. First touch or Last touch

  2. the parameter (utm_source, utm_medium, utm_campaign, utm_term or utm_content)

  3. the comparison: is a specific value, is known (has any value) or is unknown (was never recorded)

Some examples:

  • Everyone whose first touch utm_source is google — supporters originally won through Google ads.

  • Everyone whose last touch utm_campaign is spring-appeal — people most recently activated by that campaign, e.g. for a follow-up mailing.

  • Everyone whose first touch utm_source is unknown — supporters who arrived organically or through untagged links.

Like all target audiences, these update automatically: as soon as a new interaction changes a person's attribution, their memberships are recalculated.

Filtering by the source of one specific interaction

First and last touch describe a person's overall journey — but they move as the person keeps interacting. When you want to evaluate one concrete campaign, filter the interaction itself instead: every activity-based filter (signed up on a landing page, donated, purchased, answered a survey, voted, submitted content) has a "coming via" option next to its date and count filters.

Switch it on, pick the parameter and choose is a specific value or is known (any value). The filter then only counts interactions that carried those parameters:

  • Signed up on landing page X coming via utm_campaign is spring-appeal — exactly the people your spring appeal converted on that page, no matter what they did before or since.

  • Donated coming via utm_source is facebook — donors whose donation itself came through Facebook, e.g. to measure what a specific ad budget produced.

  • Signed up coming via utm_source is known — all signups that arrived through any tagged link, as opposed to organic ones.

Rule of thumb: use UTM Attribution (first/last touch) to describe people, and the "coming via" option to describe conversions. The "coming via" attribution is frozen at the moment of the interaction and never changes afterwards — ideal for evaluating a specific ad spend. It combines freely with the date and count filters, e.g. "donated in the last 30 days coming via google".

Using attribution in workflows

Both filters are available in workflow condition nodes. For example, start a workflow when someone signs up, then branch: supporters whose signup came via your newsletter get one welcome journey, paid-ad signups get another.

Sending parameters through the API

If you create people through the CamBuildr API, the tracking parameters can simply be sent as fields of the request body — handy when you forward form data from another tool as-is:

{ "email": "[email protected]", "utm_source": "partner-site", "utm_medium": "referral" }

Alternatively, group them in a tracking object to keep them clearly separated from the person's own fields:

{ "email": "[email protected]", "tracking": { "utm_source": "partner-site", "utm_medium": "referral" } }

Both forms work on the people endpoint and the tracking-link endpoint; if both are present, the top-level fields win. Either way the parameters are stored on the created action exactly like parameters captured on a landing page, and feed the person's first/last touch the same way. The click IDs (fbclid, gclid, li_fat_id) are accepted in both forms as well.

Good to know

  • Use a consistent, lowercase naming scheme (facebook, not sometimes Facebook) — filters match exact values.

  • The first set of parameters a visitor arrives with is kept for their browser session; opening the same page later in a new session or on another device counts as a new touch.

  • Parameter values are stored up to 255 characters; longer values are shortened.

  • Attribution from historical form signups that already carried UTM parameters is included, so first/last touch may already be filled for existing supporters. The "coming via" interaction filter applies to donations, surveys and other non-form interactions recorded from the feature release onwards.

Did this answer your question?