Southwest Airlines Plans Assigned Seating Rollout with WILMA Boarding Across Houston, Cancun, Fleet

Southwest Airlines is ending its decades‑old open-seating policy and shifting to assigned seating under an initiative called Project USA after testing changes in Houston and Cancun. The carrier will use a WILMA boarding method—boarding window, then middle, then aisle seats from back to front—and simplify gate procedures by replacing numbered stanchions with just two lines. Reporting differs on the rollout timing, with some outlets citing a January 27 start (reported as 2025) and others saying the change will take effect in January 2026. First‑class travelers, loyalty members and purchasers of extra‑legroom or a dynamic “Priority Boarding” add‑on will receive earlier boarding, prompting criticism that the overhaul will advantage higher‑paying customers and hurt budget flyers. The changes coincide with cabin redesigns and new boarding‑pass displays showing seat type, and they raise questions about overhead bin space as boarding shifts to back‑to‑front loading. Separately, American Airlines is phasing out gate bag sizers (following United) to streamline boarding while still enforcing carry‑on size limits and contending with baggage mishandling concerns.