Warning for anyone using a customer owned modem with Comcast: Be sure you keep your receipts and original packaging.
I recently canceled service and switched to AT&T Fiber. It was actually an unexpectedly easy process. But when I dropped off my cable box at a Comcast store, they asked me for my modem. The one that I bought myself. The person taking receipt of my equipment was fine when I said I owned my modem, and just "put a note" on my file.
... then I get a collections letter, explicitly related to the "unreturned" modem. Despite having no history of receiving a rental modem, and no monthly surcharge for modem rental on any of my years-long billing history, they refused to budge. I happened to still have the original box with the serial number on it and that combined with a printout of my Amazon order from back then was enough to at least to successfully dispute the debt on my credit reports. But it wasn't enough for Comcast, and I'm sure I'll still have to pay that bill and put down a giant deposit if (when) I move somewhere that forces me back to Comcast.
They did something similar to me too. I dropped off the modem, with my two small kids on hand, and forgot to grab a receipt. I figured dropping it off in person would leave no room for doubt. That was not correct.
A few months later, I'm getting threatening calls that I need to return the modem. I call them and the rep says "Oh, thanks, we will note that you returned it." So, they just send a collection notice and don't actually keep a record you have returned it inside their own systems.
In my case, it was the HD receiver. The Comcast guy was surprised I asked for a receipt, and was shocked when I checked the serial number on the modem vs what was on the receipt. They matched, as they should.
Then they still tried to ding me for an unreturned equipment and when I called they said 'it takes 2 - 3 months for it to come off your account'. It eventually did fall off, but was insane for hand delivering it to Comcast/Xfinity.
Had an almost identical experience to this. They seem to have no communication between their departments that sell you the product and those that collect it when you're done using their services.
I recently canceled service and switched to AT&T Fiber. It was actually an unexpectedly easy process. But when I dropped off my cable box at a Comcast store, they asked me for my modem. The one that I bought myself. The person taking receipt of my equipment was fine when I said I owned my modem, and just "put a note" on my file.
... then I get a collections letter, explicitly related to the "unreturned" modem. Despite having no history of receiving a rental modem, and no monthly surcharge for modem rental on any of my years-long billing history, they refused to budge. I happened to still have the original box with the serial number on it and that combined with a printout of my Amazon order from back then was enough to at least to successfully dispute the debt on my credit reports. But it wasn't enough for Comcast, and I'm sure I'll still have to pay that bill and put down a giant deposit if (when) I move somewhere that forces me back to Comcast.