Switching carriers question

Hi! I have ATT but I’m looking to switch carriers soon mainly because I get a discount that would make my cell phone plan cheaper at Verizon. My phone is completely paid off, but I have a tablet line and the tablet is not paid off. For what it’s worth I literally never even use the tablet anymore. Wish I could just get rid of the line.

Does anyone know how switching works if I have a tablet that’s still in installments ? I’m assuming my only option is to pay it all off first but didn’t know if there were other options. Thanks!