The NBA's Board of Governors has opened its first formal vote on expanding the league to 32 teams, with Seattle and Las Vegas confirmed as the only two markets under active consideration.

The two-day ballot, which opened Tuesday in New York, requires 23 of the league's 30 governors to approve a resolution formally opening a bidding process for both new franchises.

If the vote clears that threshold, it sets in motion one of the most consequential restructures in the league's history - returning professional basketball to Seattle 18 years after the SuperSonics departed for Oklahoma City and delivering Las Vegas its first major professional basketball franchise.

Both teams are targeted to begin play in the 2028-29 season, pending a final ratification vote expected before the end of 2026.

The $10 Billion Price of Entry

Each new franchise is expected to carry a price tag of somewhere between $7 billion and $10 billion (around AUD $10.5-15 billion), according to industry insiders.

That sum would be divided among the existing 30 owners, with each reportedly in line to receive something like $300 million from expansion proceeds. Commissioner Adam Silver confirmed the league's intentions late last year, saying in December: "Not a secret, we're looking at this market in Las Vegas. We are looking at Seattle."

Las Vegas has built significant NBA betting credibility over more than two decades - hosting the Summer League since 2004, the 2007 All-Star Game, and the NBA Cup finals since 2023 - without ever landing a permanent franchise. Industry executives project both markets would rank among the NBA's top eight revenue generators.

Seattle's situation carries far more history. The SuperSonics, who won the city's only NBA championship in 1979 and played from 1967, were sold to an Oklahoma City investment group led by Clay Bennett in 2006 for $350 million.

Bennett relocated the franchise after a failed push for public arena funding, with NBA owners voting 28-2 to approve the move. A subsequent settlement required the ownership group to pay $45 million to break the existing lease, and by agreement the SuperSonics name and team history would remain in Seattle for any future franchise to inherit.

What Seattle and Las Vegas Need Next

Washington Governor Bob Ferguson met with Commissioner Silver the day before voting opened, with his spokesperson describing the exchange as "productive." Ferguson has publicly identified returning the SuperSonics as a top "priority."

The Seattle Kraken ownership group has also launched One Roof Sports and Entertainment as a parent organisation, taking majority control of Climate Pledge Arena - which was built specifically to NBA specifications - signalling clear intent to front a formal expansion bid.

A resolution in favour does not finalise expansion. It formally opens the bidding process for both cities, with a second and final vote - expected by year's end - required to lock in the franchises.

Silver has indicated the league will decide whether to add one or both franchises before the end of 2026. Adding two Western Conference markets would also likely require an existing team to shift to the Eastern Conference, with Minnesota, Memphis and New Orleans identified as geographically logical candidates.

Both franchises, if approved across both votes, are scheduled to tip off for the first time in the 2028-29 NBA season. For those looking to understand how to bet on the NBA, expansion could significantly reshape the betting landscape with new teams entering the fold.