Boeing usually quotes two class configurations. The 767-200 is 216 seats and 767-300 is 261. That tells us the plane they are proposing is almost identical in size to the 767-200/300 but with less range.
I would suggest not getting distracted when people start quoting single class seat counts that make the A321 sound similar in size, when in reality there is a gap.
Especially when they post high single class seat counts (with accompanying baggage) and maximum range in the same sentence.
Leeham spelled out the trade-offs:
With our trip through the realities of the Airbus A321neo, we have learned the different trades that have to be considered for an airline that buys a A321LR for Trans-Atlantic missions. A big influence will be the cabin and optional equipments choices. Airbus advertises the A321LR at launch as 16 business class (36 inch pitch) and 190 economy (30 inch pitch) for a total of 206 seats. Our model shows that the empty weight of the A321LR has to stay below 52t for this to work, so Airbus assumes a typical “OEM show room” configuration with very basic assumptions for seat weights, IFE, galley equipment, aircraft options, quite different from the typical Boeing 757-200W configurations we compared with from Delta Air Lines and United Airlines in October.
We can also see that Airbus has assumed non LD3-45 loaded passenger bags. The bags simply does not fit for 206 passengers in a containerized concept with normal assumptions for bags per passenger and bags per container. It requires nine containers free and we would only have seven after the three fuel tanks have been installed. With bulk-loaded bags, including using the bulk cargo area, the bags for 206 passengers will fit with a bit of room to spare.
Ref: https://leehamnews.com/2015/01/15/airbu ... ats-there/
So you can get 206 passengers in two classes (note: not the 240 one-class count) to max range (4000nm still air, 3500nm realistic) if you also use an unrealistic showroom configuration and do not use containers.
We shall see exactly what Boeing presents, but if you presume what we know from Boeing (two main NMA versions: a 225-seat model with a 5,000 nm range and a larger, 275-seat version with a range of roughly 4,500 nm) is using similar assumptions (two classes, showroom configuration, bulk loading) there is a meaningful gap in terms of range and passenger count (and presumably, efficiency too).