When the San Francisco 49ers head to Seattle Sunday for an NFC Championship matchup with their division rival, CenturyLink Field may be more hostile than they remember.

Seahawks.com announced Saturday tickets for the game would only be available to fans with billing addresses in WA, OR, MT, ID, AK, HI and British Columbia and Alberta in Canada when they went on sale at noon Monday. As a result, San Francisco fans hoping to make the trek up to Washington Sunday will have to look to other means if they want to attend the game. Niners fans in California can still buy tickets through secondary ticket markets like Stub Hub, NFL Ticket Exchange and TiqIQ — although at a much higher price. While the face value of a ticket to Sunday’s game could be purchased on the team’s official website for as low as $222.95, the lowest price for a ticket to the NFC Championship on StubHub.com was $461.50 as of 6 p.m. Sunday.

To many San Francisco fans, the move seemed to be an effort by Seattle to maintain its “12th man” home-field advantage against a 49ers team that has traveled well so far in the playoffs. “I’m sure they’re not concerned about the appearance, but it still looks kind of weak,” wrote NinersNation.com's David Fucillo on Saturday.

Still, while Seattle’s ticketing move may have the largest effect next weekend, the Seahawks’ decision not to sell to their opponent’s fans is not uncommon. In the AFC Championship Sunday, the Denver Broncos will only be allowing fans from eight neighboring states to buy tickets to their game in Denver against the New England Patriots. More than 96 percent of Broncos season ticket holders elected to purchase tickets, however, putting a greater limit on the number of available tickets.