This is only a cable modem. It permits you to connect to your internet provider's cable. You can connect this cable modem to a router with Wi Fi capabilities (which you must purchase separately) and if your cell phone provider and internet provider are compatible with Wi Fi calling (most are) you can make Wi Fi calls. The key component here is the router, not the cable modem. This cable modem with a good Wi Fi router does a great job with Wi Fi calling, but you have to have the Wi Fi router also.