The New York Democrat says passengers who purchase new "basic" fares offered by United Airlines and American Airlines won't be able to store carry-on baggage in the overhead bins.
He says he worries other airlines will follow suit and that one day all passengers might have to pay extra if they want to stow a suitcase overhead.
Schumer said Sunday that all passengers should be allowed to use the overhead bins without extra charges.
The airlines argue that the new "basic" fares are simply a way to give passengers a cheaper alternative to standard fares, which come with overhead bin privileges.