UTM parameters

UTM parameters are customized tags appended to URLs that carry campaign metadata—source, medium, name, and more—to your analytics platform. They don't affect link behavior; they just tell you where your traffic comes from.

Bloomreach works with UTM parameters in 2 ways: it reads them when visitors arrive on your site, and it automatically appends them to links in outbound campaigns.

How UTM parameters work

Inbound tracking: session start events

When a visitor comes to your website with UTM parameters present in the URL, the JS SDK automatically the JS SDK automatically parses them into attributes of the session_start event:

• utm_campaign
• utm_source
• utm_medium
• utm_content
• utm_term
• campaign_id
• gclid

For details on these attributes, see the System events article.

To track additional URL parameters, follow the guide to tracking events.

Automatic UTMs for outbound channels

When you send messages via the following channels, the UTM tags below are added to hyperlinks automatically:

• Email
• SMS (using Campaign link shortener)
• Mobile push
• Browser push
• RCS
• WhatsApp
• App inbox

The following tags are added:

• utm_campaign
• utm_source
• utm_medium

For example, if you send an email with an email action node named "April newsletter" with a link to https://bloomreach.com/, the final link will look like this:

https://bloomreach.com/utm_campaign=april%20newsletter&utm_source=bloomreach&utm_medium=email

For details on link transformation, review the Mobile push notifications article.

Automatic UTM parameters

You can define default UTM parameters that apply automatically to all campaigns.

1. Go to Project settings.
2. Under Campaigns, go to General > General campaign settings > Default URL parameters.

Each parameter can be set for all channels or specific channels only.

When configured, the default parameters are automatically populated in scenario nodes and email/SMS campaign modules when Settings > Link transformation is set to Auto.

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Important

Each UTM parameter can only be specified once per channel.

To define your own values, set Settings > Link transformation to Manual.

Adding other UTM parameters

To add UTM parameters that aren't included by default, add them directly to the link in your campaign. For example, to add utm_id: https://bloomreach.com/?utm_id=442178.

Automatic UTM parameters are appended to the link alongside your custom tag.

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Important

UTM parameters added via campaign or project settings aren't included in the URL property of campaign events unless Universal Links are used.

Best practices

Use a consistent naming convention

• Agree on a naming guideline and share it with your team to prevent inconsistent variations (for example, "FB" vs. "Facebook").
• Use dashes instead of underscores, percentages, or plus signs. This helps browsers and search engines parse the values correctly.
• Use lowercase only. UTM values are case-sensitive. Mixed-case values create duplicate entries in your analytics.
• Keep names simple and readable. Avoid internal codes or abbreviations that aren't self-explanatory.
• Make each parameter distinct. If your campaign name already identifies the campaign, don't repeat the same information in the source.

Choose the right parameter for the job

• utm_source: The platform or vendor where traffic originates, for example, Facebook or Google.
• utm_medium: The mediums, for example, email, cost per click (CPC), social media, or SMS, affiliate, or QR code. Use it to differentiate links from paid traffic, profile info links, and posts on the wall.
• utm_term: The keyword being tracked, mainly used for paid ad campaigns.
• utm_content: Differentiates links pointing to the same URL, for example, a button vs. a text link, or two versions in an A/B test. If there are multiple links with the same URL, they should each have a different UTM parameter.
• utm_campaign: Identifies the specific campaign, promotion, or newsletter.

UTM parameter reference

Limitations

The maximum size of one UTM parameter is 200 characters.