If you're referring to BlackBerry Messenger, that is considered data and should be covered by your unlimited BB data plan. You could call customer service though and make sure your plan is set up as such.
BBM is one of the advantages that makes BB special. Enjoy!
Messages sent using BlackBerry Messenger and BlackBerry PIN to PIN Messaging are covered under customer’s data plan or feature:
- Customers with Unlimited data access plans or features: not billed any additional usage for using BlackBerry Messenger and PIN to PIN Messaging.
- Customers with Grandfathered Megabyte plans or features: messages sent using BlackBerry Messenger or PIN to PIN Messaging decrements from their data allowance