This the Basic Economy fare the other posters are referring to -- been around for over a year. If purchased on united.com, you get multiple warnings. Other online purchasing websites, things are not as clear but there are warnings -- no full size carry allowed for the BE (Basic Economy) fares. the other major carriers AA & DL offer the same types of fares as do some discount budget airlines. Southwest does not offer BE at the moment.

BE fares can make sense for some but one needs to add the extra bag fees, if any, into the total prices or have a credit card offering checked bag fee waiver.