What is Offline conversion?

An offline conversion is an outcome that happens outside the website after an ad click (a sale by phone, a qualified lead in the CRM, a signed contract) and is uploaded back to the ad platform to be matched with the related click or user. In Google Ads this is done with the GCLID or hashed customer data; in Meta, with the Conversions API.

Last updated: 20 October 2026View as Markdown

In short

Offline conversions tell an ad platform not just that a form was filled in, but whether that enquiry actually became a sale. With that signal, smart bidding learns to chase revenue-generating customers instead of cheap leads, which fills the measurement gap in long-cycle sectors such as B2B, automotive and real estate. Teams monitor match rate and upload regularity to keep it healthy. A software company, for example, uploads opportunities marked won in its CRM, with their contract value, to Google Ads so campaigns optimize for real revenue.

Key points

An offline conversion matches a result that happens off the website to the original ad click.
In Google Ads, the GCLID click ID is captured in the form and stored on the CRM lead record.
If the click ID is missing, hashed email and phone data can be used for matching.
Google Ads offline imports require the conversion to happen within 90 days of the click.
It lets campaigns optimize for real sales rather than form counts.

How does it work?

The ad click ID (the GCLID in Google Ads) is captured in the form and written to the lead record in the CRM. When the lead turns into a sale, this ID and the value of the outcome are uploaded to the ad platform. If the ID can't be captured, matching can be done with hashed email and phone.

What to watch

For Google Ads offline imports, the conversion must have happened within 90 days of the click at most. With long sales cycles, an earlier stage (e.g. a sales-accepted lead) is uploaded as the primary conversion.

Why it matters

It lets campaigns optimize for real sales rather than form counts. More detail: Google Ads offline conversion tracking, related service: Google Ads agency.

Last updated: 20 October 2026

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