How soon after releasing a number is it available for someone else to use?

At the end of your rental period for a number, the number will be released and returned to the Sinch numbers inventory. The number will then be quarantined (held back from further use) for a period of 30 days before it is available for others to use. 

Click here to learn more about how you can get access to a complete range of carefully-tested phone numbers, to use with all your communication services from Sinch.