Quebec City to New England

No, you won't find a Canada to US car rental.
I would look into train or bus options.

Is there a train from Quebec City to Vermont?

Where in Vermont are you trying to get to? I tried Burlington, VT from Quebec City and looked like you could make the trip either by bus or a combination of train & bus. Or have you plotted a route where you can do a one way drop rental car from Quebec City to a town close to the US border & take a bus or train from there by crossing the border. Both sound rather tedious, but my sister won't fly and she manages to do these type of trips all the time. A couple years ago she and her husband took Amtrak to Boston (I think that was where they transferred) to a train that took them to Toronto and then they took Canadian Via Rail from Toronto to Vancouver, then back to the U.S. & took the Empire Builder back to MN.

I don’t think there is a train from Quebec to Vermont except by a totally impractical route that would take forever, such as, Canadian train to Montreal, Amtrak through New York State to New York City, then back north on Amtrak’s service up to Vermont which terminates in St. Albans.

Thanks for the info. It verifies what I have found with my own research.

in fall 2024 I looked for a one way rental car from Boston to Quebec and it was possible. Maybe that was because of an airline strike