Microsoft Click ID (msclkid)

The Microsoft Click ID, carried in a URL parameter named msclkid, is a unique code that Microsoft Advertising adds to your landing-page URL each time someone clicks one of your ads. The mechanism is called auto-tagging: when a visitor clicks, Microsoft appends the msclkid to the destination URL automatically, and that identifier is then picked up by the Universal Event Tracking (UET) tag on your site. From that point on, the UET events fired by that visitor carry the click ID, which lets Microsoft tie a later conversion back to the exact click that started it. The value is a GUID with an extra byte marking whether it is new to the session, and auto-tagging of the Microsoft Click ID is enabled by default on Microsoft Advertising accounts.

The Microsoft Click ID matters because it makes conversion attribution robust. Cookie-based tracking can break across browsers and privacy settings, so tying a conversion to a click by cookie alone leaves gaps. The msclkid gives Microsoft a durable, click-level thread that works even where the standard cookie cannot, so fewer conversions fall through the cracks and reporting is more complete. Just as important, it unlocks offline conversion tracking: because the click ID is a stable identifier you can capture and store, a click that becomes a sale in your CRM days later can be reconnected to its original click by uploading the stored msclkid with the offline conversion, crediting the exact click that started the journey.

The Microsoft Click ID is the direct counterpart to Google's gclid, and they play the same role on rival platforms. The gclid is Google Ads' auto-tagged click identifier; the msclkid is Microsoft Advertising's. Both are unique per-click parameters appended to your landing-page URL, both let the platform tie a conversion back to a specific click, and both power offline conversion import — you store the ID at click time and upload it later with the sale. The practical rule is simple: send the gclid to Google's conversion tools and the msclkid to Microsoft's. Mixing them up — trying to upload a msclkid to Google or a gclid to Microsoft — silently fails, because each platform only recognizes its own click identifier.

The identifiers also lean on each platform's own tag. The msclkid is read by Microsoft's UET tag; the gclid is read by Google's tag and analytics. If a click ID lands on your URL but the corresponding tag is missing or misfiring, the thread breaks and the conversion goes unattributed. That is why the two systems are best kept parallel but separate: one platform's click ID, one platform's tag, one platform's conversion upload. Keeping them straight — and preserving the parameter as visitors move through your site so it survives to the conversion — is what makes cross-engine performance reporting trustworthy rather than a pile of half-attributed clicks. The msclkid is Microsoft's half of that story.

Using the Microsoft Click ID well starts with making sure auto-tagging is on (it is by default) and the UET tag is firing correctly on every landing page and conversion page, so the click ID actually gets captured and matched. Preserve the msclkid as visitors navigate your site, since a lengthy path or a stripped query string can lose the parameter before the conversion happens. For offline sales, capture and store the msclkid at the moment of the click — typically in a hidden form field that flows into your CRM — so you can upload it later with the converted sale to import the offline conversion. Done this way, the click ID closes the loop between a paid click and revenue that lands days or weeks afterward.

The failure modes are a broken or missing UET tag (so the click ID is never read), a landing page or redirect that strips the msclkid before it can be captured, confusing it with Google's gclid and uploading the wrong ID, and forgetting to store the msclkid at click time so offline conversions can never be reconnected. Privacy settings and consent also govern whether tracking runs at all, so respect them. The discipline is straightforward: keep auto-tagging enabled, keep the UET tag healthy, preserve and store the click ID through the journey, use Microsoft's tools with Microsoft's ID, and honor consent — then conversion tracking, online and offline, holds together.

Microsoft Click ID (msclkid) — Microsoft Advertising's auto-tagged per-click identifier — mirrors Google's gclid and powers both online and offline conversion attribution.

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