Determine the required accuracy
A static number helps separate a channel or placement. The dynamic approach associates a number with a visit according to the system's rules, but depends on the pool of numbers, the retention period, and the available data. A repeat call after a long time may have a different attribution reliability.
Continue with: UTM in CRM: preserve the source of an enquiry.
Check display and call
Check the visible number and link tel:, mobile browser, different pages and returning visitor. If the script did not load, the primary contact should remain functional. Test multiple concurrent sessions to understand the behavior when the number pool is insufficient.
Continue with: Google Ads conversions: are genuine enquiries counted?.
Map the call to CRM
Not only the source and duration are important, but also the result of the conversation. A short call is not always a bad call, and a long call is not necessarily a sale. Agree on qualification and conversion transfer rules, control duplicates and unknown sources. Consider the cost of phone numbers and the service separately from setup.
Is call tracking a replacement for UTM and CRM?
No. It adds information about calls, and a correct assessment requires coordination of sources, events and further work with the client.