American Airlines
American Airlines generally offers 31-32 inches of seat pitch in its economy cabin. Although it does operate some of its Airbus A319s and Boeing 757s with 30 inches of pitch.
Delta Air Lines
Like American, Delta is also operates a fleet with 31-32 inches of seat pitch on most of its planes. However, the airline does operate some Airbus A319s, A320s, Boeing 757s, and McDonnell-Douglas MD90s with 30-31 inches of pitch.
United Airlines
United Airlines also operates a fleet with mostly 31-32 inches of seat pitch. At the same time, it does operate some Boeing 737, Airbus A319, Bombardier CRJ700, and Q400 aircraft with 30 inches of pitch.
Southwest Airlines
Southwest operates a fleet consisting of only Boeing 737s with most versions offering 32-33 inches of seat pitch. However, its 737-700s offering 31 inches of pitch.
JetBlue
Jetblue offers 32-33 inches of seat pitch across its fleet. Although some of the boutique carrier's Airbus A320s have 34 inches of pitch in economy.
Virgin America
Virgin America operates a fleet of Airbus A319 and A320 aircraft. The Burlingame-based boutique carrier offers 32 inches of seat pitch in economy on all aircraft.
Alaska Airlines
Alaska airlines operates a fleet consisting mostly of Boeing 737 and Embraer 175 aircraft. Most offer 32 inches of seat pitch. However, the 737-800, which represents a sizable chunk of its fleet, offers 31-32 inches.
Hawaiian Airlines
Hawaiian Airlines operates a fleet consisting mainly of three aircraft - the Airbus A330, Boeing 717, and 767. The Airbus A330 offers 31-32 inches of seat pitch while the Boeing 717 offers 29-31 inches. The Hawaiian's Boeing 767 offer 32 inches of seat pitch in coach.
Allegiant Air
Allegiant Air operates a fleet of Airbus A320-family, Boeing 757, and McDonnell-Douglas MD80 jets. The discount carrier offers 30 inches of seat pitch in economy across is fleet.
Frontier Airlines
Frontier Airlines operates a fleet of Airbus A320-family jets. According to SeatGuru, the low-cost carrier's A319s offer 28-31 inches of seat pitch while its A320s offer 28-29 inches. On the other hand, its A321s offer 30-32 inches of pitch.
Spirit Airlines
Like Frontier, Spirit also operates a fleet consisting exclusively of Airbus A320-family jets. The discount carrier offers 28 inches of seat pitch in coach across its whole fleet.