United A321neo Coastliner: Polaris on Transcon Flights, and Why It Is Late (2026)
✈️ Quick Verdict
Status: not flying yet. It was due in summer 2026; United has confirmed Airbus delivery delays and given no new date.
Aircraft: Airbus A321neo — 161 seats: 20 Polaris, 12 Premium Plus, 129 economy
Layout: Polaris 1-1, every suite on the aisle · Premium Plus 2-2 · economy 3-3
Routes: San Francisco and Los Angeles to Newark; New York JFK from 2027
Closest cabin today: the United A321XLR, which United describes as nearly identical
On the ground: Polaris lounge access for Polaris passengers — a first for a United domestic flight
The catch: the jet is late
United unveiled the Coastliner in March 2026 and said the first one would enter service that summer. It has not. In late August United confirmed the aircraft had been held up by delivery delays at Airbus and would not give a timetable — only that it would start flying as soon as it arrived.
Until then, a United transcon booking does not get you a Coastliner, whatever the marketing says. United has said it may use its A321XLR on some limited cross-country flights in the meantime, and that it has no long-term plan to fly the XLR domestically. If your flight shows an A321XLR, read the A321XLR guide: its 20 Polaris suites have doors, and in row 32 the two middle seats are not seats at all but a fixed table.
What is on board
United’s standard A321neo carries 200 seats in two classes. The Coastliner carries 161 in three:
| Cabin | Seats | Layout | What it is |
|---|---|---|---|
| Polaris | 20 | 1-1 | Lie-flat suites, every one with its own aisle, with lower suite walls to keep the cabin open |
| Premium Plus | 12 | 2-2 | United’s premium economy recliner, new to its domestic narrowbodies |
| Economy | 129 | 3-3 | Including about 36 Economy Plus seats with extra legroom |
United removed three economy seats to fit a self-service snack bar at the back of the cabin. Polaris passengers get United Polaris lounge access, which United has never offered on a domestic flight. United has not said whether the Coastliner’s Polaris suites have doors; the A321XLR’s do.
Where it will fly
United says the Coastliner will fly only on its premium transcon routes: San Francisco and Los Angeles to Newark, with New York JFK added when that service starts in 2027. In March United planned about 40 Coastliners in service by early 2028, out of 50 A321neos on order. The delay makes that timeline uncertain.
How it compares on transcon
| United Coastliner | United A321XLR | American A321XLR | Delta A321neo (transcon) | |
|---|---|---|---|---|
| Status | Delayed, no date | Domestic from September 2026, international from December | Flying | Lie-flat seats awaiting certification |
| Lie-flat seats | 20 Polaris, 1-1 | 20 Polaris, 1-1, with doors | 20 Flagship Suites, 1-1, with doors | 16 Delta One planned |
| Premium economy | 12, 2-2 | 12, 2-2 | 12, 2-2 | 12 planned |
| Economy | 129 | 118 | 123 | 120 planned |
| Total | 161 | 150 | 155 | 148 planned |
| Lounge | Polaris lounge | Polaris lounge | Flagship lounge | Delta One lounge |
Delta is stuck in a similar place. Its lie-flat Delta One A321neo has been waiting on certification, so since May 2026 seven of the jets have flown a stopgap layout with 44 domestic First seats instead. See the Delta A321neo guide and the American A321XLR guide for row-by-row detail on the jets that are flying.
Picking a seat when it arrives
The Coastliner’s row numbers have not been published, so there are no row picks yet. What the layout already tells you:
Polaris: with a 1-1 layout, every suite is both a window and an aisle seat, so there is no bad pairing to avoid. The decision will come down to distance from the galley and lavatory, as it does on the XLR. Premium Plus: 2-2, so a solo traveller should take an aisle. Economy: the snack bar at the back will bring passing traffic to the last rows.
Check the aircraft type on your booking before you pay for a Polaris fare on these routes. Until the Coastliner arrives, the plane on the day decides what you get.
Frequently asked questions
When will the United Coastliner start flying?
United has not said. It was due in summer 2026, but United confirmed in August that Airbus delivery delays had held it up, and gave no new date.
How many seats does the Coastliner have?
161: 20 Polaris lie-flat suites in a 1-1 layout, 12 Premium Plus seats in 2-2, and 129 economy seats in 3-3.
Which routes will the Coastliner fly?
San Francisco and Los Angeles to Newark, with New York JFK added in 2027.
What flies instead while the Coastliner is delayed?
United has said it may use the A321XLR on some limited cross-country flights. Its cabin is close to the Coastliner’s: 20 Polaris suites with doors, 12 Premium Plus and 118 economy.
Do Coastliner passengers get Polaris lounge access?
Yes. Polaris passengers on the Coastliner can use United Polaris lounges, a first for United domestic flying.