As most of us would expect, an EV will have much lower mileage while towing. Rivian says about 50% lower. This this real world test shows: "with a range of 315 miles (505km) on a full charge, that works out to just 118 miles from the 135kWh battery pack, or about 62% range loss."
The Rivian R1T has a towing capacity of 11,000 lbs. According to the company’s website, towing at that weight will reduce range “by about 50%.” In the first real-world R1T towing test, that number is [...]