Why do third-party tracking URLs lose UTMs?
Third-party tracking URLs, such as email click trackers, link shorteners and affiliate redirects, wrap your destination link. Some strip or mangle query strings through security filters, encoding problems or redirect defaults, so your UTM parameters never reach the page. Test each tracker and configure it to keep parameters. Tools like Trakt build tagged short links.
What is a third-party tracking URL?
A third-party tracking URL is a redirect link created by a platform you don't control—your email marketing tool, your affiliate network, your link management service, or your social media scheduler. The platform inserts its own tracking domain between your ad or email and your landing page, so it can measure clicks before forwarding users to your site.
Common examples:
- Email click tracking:
click.mailchimp.com/...ort.hubspotemail.net/... - Link shorteners:
bit.ly/...ortinyurl.com/... - Affiliate networks:
aff.platform.com/click/... - Social scheduling tools:
sched.link/...orbuff.ly/...
These third-party tracking URLs serve a legitimate purpose: they let the platform measure engagement without requiring access to your website analytics. The problem is that many of them strip query parameters (including your UTM parameters) during the redirect, either by design or misconfiguration.
When that happens, this is what your user experiences:
- They click your email link:
click.mailchimp.com/.../redirect?url=yoursite.com/offer?utm_source=email&utm_campaign=q4_nurture - The third-party tracker logs the click
- The redirect sends them to:
yoursite.com/offer(UTMs gone)
Your analytics and CRM see a visitor with no source data. The lead gets credited to "Direct" traffic. The campaign that actually produced the lead is erased.
- Campaign linkEmail
Your campaign uses a third-party tracker
The link goes through the email platform's click tracker before reaching your site.
click.mailchimp.com/...?url=example.com/offer?utm_source=email&utm_campaign=q4_nurture
- Third-party redirectPreserves
The tracker preserves query parameters
The redirect is configured to forward UTMs instead of stripping them.
- Landing pagePreserves
Your site keeps the UTMs
No additional redirects strip the parameters. The source data reaches your forms.
- Form leadTrakt
Hidden fields capture attribution
The lead is created with source data intact.
- utm_source
- utm_campaign
- q4_nurture
- Closed wonWon
Revenue is tied to the campaign
The campaign gets credit because attribution survived every redirect.
- source
- q4_nurture
- deal value
- $16,500
Each redirect is a place where UTM parameters can be stripped. When all three hold, attribution survives.
Why third-party tracking URLs strip UTM parameters
Third-party tracking URLs strip UTM parameters for three reasons: security, simplicity, or misconfiguration.
1. Security filters
Some platforms strip query parameters as a security measure to prevent malicious code injection through URL parameters. This is well-intentioned but breaks attribution for legitimate marketing campaigns. The platform protects itself at the expense of your tracking.
2. Character encoding issues
UTM parameters contain special characters (&, =, ?) that need to be properly encoded when passed through a redirect. If the third-party platform doesn't URL-encode the destination properly, those characters get interpreted as part of the redirect URL structure instead of being preserved as query parameters. The result: your UTMs are malformed or stripped entirely.
3. Redirect configuration defaults
Many third-party tracking URLs default to stripping query parameters unless explicitly configured to preserve them. If you use the platform's default link format without checking the redirect behavior, you discover the problem only after your campaign launches and the attribution is already broken.
How to test whether a third-party tracking URL preserves UTM parameters
Before you send any campaign through a third-party tracking URL, test whether it preserves UTM parameters. The test takes 30 seconds:
- Build a test destination URL with UTM parameters:
yoursite.com/test?utm_source=email&utm_campaign=test - Run it through the third-party tracker (create the redirect link in your email platform, link shortener, or affiliate network)
- Click the third-party tracking URL and check the final URL in your browser's address bar
If the UTMs are visible in the final URL (yoursite.com/test?utm_source=email&utm_campaign=test), the redirect works. If they're missing, the third-party tracker is stripping them.
Test on both desktop and mobile. Some platforms handle mobile redirects differently, especially on iOS where Safari and in-app browsers have different referrer handling.
How to fix third-party tracking URLs that strip UTM parameters
If your test shows that a third-party tracking URL strips UTM parameters, you have three options: fix the redirect configuration, switch to a tracking platform that preserves parameters, or bypass the third-party tracker entirely.
Option 1: Configure the platform to preserve query parameters
Most modern email platforms, link shorteners, and affiliate networks have settings that control whether query parameters are preserved during redirects. The setting is usually called "preserve query string," "append parameters," or "forward URL parameters."
For example:
- Mailchimp: Check "Track clicks" settings and ensure "Forward query parameters" is enabled
- HubSpot: Email click tracking preserves UTMs by default, but check Marketing Email settings
- Bitly: Use the "pass-through parameters" option when creating the link
- TinyURL: Premium accounts support parameter preservation; free accounts don't
Check your platform's documentation for the specific setting name. If the platform doesn't support parameter preservation, move to option 2 or 3.
Option 2: Switch to a tracking platform that preserves parameters by default
If your current platform strips UTM parameters and won't let you fix it, switch to one that handles redirects correctly. Modern link management platforms (Rebrandly, Short.io, BL.INK) preserve query parameters by default because they're built for marketers who need attribution.
The migration cost is usually lower than the cost of broken attribution across every campaign.
Option 3: Bypass the third-party tracker for critical campaigns
If you can't fix the redirect and can't switch platforms immediately, bypass the third-party tracking URL for campaigns where attribution matters most. Use direct links with your own UTM parameters, and rely on your website analytics and CRM for click tracking instead of the third-party platform's dashboard.
You lose the third-party platform's click metrics, but you keep the attribution data that actually drives business decisions.
If you want your tagged links built to one naming rule, pre-register for Trakt.
How to structure UTM parameters when using third-party tracking URLs
When you know a campaign will go through a third-party tracking URL, structure your UTM parameters to make them harder to break. Use these practices:
1. Keep UTM values short and simple
Long UTM values with special characters are more likely to get malformed during redirects. Instead of utm_campaign=Q4_Email_Nurture_Sequence_2026, use utm_campaign=q4_email_nurture. Lowercase, underscores only, no spaces.
2. Avoid nested parameters
Don't build a destination URL that already has query parameters, then pass it through a third-party tracker that adds more parameters. The nesting can confuse redirect logic. Structure your links so the UTMs are the only query parameters on the final destination URL.
3. URL-encode your destination before passing it to the tracker
If you're building third-party tracking URLs programmatically (through an API or script), URL-encode the entire destination URL including UTMs before passing it to the tracker. This ensures special characters are properly escaped and survive the redirect.
Where to go from here
The easiest way to avoid third-party tracking URL problems is to use platforms that preserve attribution by default and to test every redirect before launching a campaign. If you manage campaigns across multiple platforms (email, social, affiliate networks), standardize on tools that don't break your tracking.
For teams managing attribution across dozens of third-party platforms, Trakt's tracking system handles parameter preservation automatically and provides unified reporting across every channel, so you don't have to debug redirect configurations for every tool in your stack.
Frequently Asked Questions
What is a third-party tracking URL?
A third-party tracking URL is a redirect link managed by an external platform (email provider, link shortener, affiliate network) that wraps your destination URL so it can measure clicks before forwarding users to your site. The problem is that many third-party trackers strip UTM parameters during the redirect, which breaks attribution by the time the click reaches your CRM.
How do I know if a third-party tracking URL is breaking my attribution?
Build a test URL with UTM parameters (yoursite.com/test?utm_source=test&utm_campaign=test), run it through the third-party tracker, click the link, and check the final URL in your browser. If the UTMs are missing, the tracker is stripping them. Test on both desktop and mobile before launching any campaign.
How do I fix a third-party tracking URL that strips UTM parameters?
Three options: configure the platform to preserve query parameters (check for settings like "forward URL parameters" or "preserve query string"), switch to a tracking platform that handles redirects correctly (Rebrandly, Short.io, BL.INK), or bypass the third-party tracker entirely for critical campaigns and use direct links with UTM parameters.
Do all email platforms strip UTM parameters?
No. Modern email platforms (Mailchimp, HubSpot, ActiveCampaign, Klaviyo) preserve UTM parameters by default or have settings that let you enable it. Older platforms or free-tier tools are more likely to strip parameters. Always test your specific platform before launching a campaign that relies on UTM attribution.
