# utm_source

> The UTM parameter that names who sent the visit: a site, app, newsletter or partner.

Source: https://datacenter.so/glossary/utm-source

`utm_source` answers "who sent this visit?": `google`, `facebook`, `instagram`, `newsletter`, `partner-name`. It is one of the three parameters Google says to always set, with `utm_medium` and `utm_campaign` ([Google](https://support.google.com/analytics/answer/10917952)).

Keep it to the platform or list itself, lowercase, with one spelling. `Facebook`, `facebook` and `fb` become three rows in your reports. Put the kind of channel in `utm_medium`, not here.

## Related terms

- https://datacenter.so/glossary/utm-medium
- https://datacenter.so/glossary/utm-campaign
- https://datacenter.so/glossary/utm-parameters