Step 1
Obtain Twilio phone numbers
Purchase a pool of phone numbers from the Twilio self-service portal or the Twilio Phone Number API. You can search for phone numbers within a specific country and area code.
Step 2
Map Twilio phone numbers
Choose and implement your phone number allocation strategy. The most typical is a 1:1 mapping between an agent and a Twilio number. In this example, an advertiser’s number is mapped to the Twilio phone number.
Step 3
Implement counters
Set up counter linked to the webhook that Twilio sends your app to count the number of incoming calls.
Step 4
Publish Twilio phone numbers in your ads or web pages
You are now ready to publish the Twilio phone numbers on your ad, web page, or any other content.
Step 5
Interested buyers call the listed number
When the listed number is called, Twilio receives the call and sends a webhook to your web server. The counter associated to the Twilio number will be updated.
Step 6
Your web server returns the mapped phone number
Your web server looks up the advertiser’s private phone number mapped to the Twilio number and returns a TwiML to that advertiser’s number. Twilio initiates a call between the buyer and that advertiser.

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