When using Call Only Ads, is it correct that no tracking code needs to be added to my website to track conversions?
Google's call tracking acts as the conversion code, so when their unique number is dialed, it's counted as a conversion.
If you use the call tracking numbers Google provides you'll probably have the call conversions listed in your account.
But Google may not provide tracking numbers in all countries. If you use another call tracking software, you'll get the conversions in that software and you can also have them send the conversion into Google Ads as needed.
I try to have conversions set up on Google Analytics and import that into Google Ads instead of using Google Ads conversions.
Here's more info: https://support.google.com/google-ads/answer/2454052
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