Do you offer free text messages for opt-in messages?

The carrier charges no matter if it is an incoming message or outgoing message, so all message type count toward your monthly amount, even opt-ins, age gating, and replies.

If you are a S.H.A.F.T. C company please check out this article on increased rates from the carriers starting June 1, 2023.  https://ottertext.com/articles/navigating-the-price-increase-for-unregistered-10dlc-numbers-a-comprehensive-guide