Three of the world’s biggest cruise lines on Thursday said they expected to restart cruises to Alaska in July, citing new federal legislation that could make it possible.Holland America, Princess Cruises and Carnival Cruise Line – all owned by cruising giant Carnival Corp. – simultaneously announced what, at first blush, appeared to be definitive plans to restart sailings to Alaska out of Seattle on July 24, July 25 and July 27, respectively.Still, the sailings aren’t quite as definitive as they seem. They remain contingent on approval from the U.S. Centers for Disease Control and Prevention (CDC). The agency has been blocking cruise ships from sailing in U.S. waters for more than a year, citing worries about the spread of COVID-19 on ships. So far, it has given no such approval to any cruise line.For more cruise news, reviews and tips, sign up for TPG’s new cruise newsletter.A spokesperson for Carnival Corp. told TPG that the company was optimistic that approval for Alaska sailings from the CDC was not far off. The CDC and cruise lines have been in increasingly intense discussions about a restart to cruising from U.S. ports in recent weeks.“We are optimistic that we will be able to conclude our ongoing discussions with the CDC,” said Carnival Corp. spokesperson Roger Frizzell.Carnival Corp. is increasingly confident it can restart cruises in Alaska in July in part because, as of Thursday, it appears to have cleared a second hurdle to restarting such trips.The announcement from Carnival Corp. came just hours after the U.S. House of Representatives passed legislation that would allow foreign-flagged cruise ships (such as those operated by Carnival Corp.) to sail to Alaska this summer without stopping in Canada.Without the legislation, the Carnival-owned brands would have been unable to sail to Alaska this summer even if the CDC granted approval for such sailings, as Canada currently is closed to cruise ships.Sign up for our daily newsletterEmail addressSign upI would like to subscribe to The Points Guy newsletters and special email promotions. The Points Guy will not share or sell your email. See privacy policy.By law, foreign-flagged cruise ships can’t sail between U.S. ports without making a stop at a foreign port such as those in Canada. The law, the Passenger Vessel Services Act, was designed to give America’s maritime industry a monopoly on travel between U.S. ports and has been on the books since 1886.The legislation passed by the U.S. House of Representatives on Thursday temporarily waives the Passenger Vessel Services Act until Canada’s ports reopen. Similar legislation was passed by the U.S. Senate last week. The bill still must be signed by President Joe Biden to become law.Assuming President Biden signs the bill and the CDC approval for the Alaska sailings comes through, the three Carnival Corp. brands plan to operate one ship each in Alaska starting in July.Carnival Corp. said the sailings only would be open to passengers who are fully vaccinated for COVID-19. Passengers will have to show proof they have received a final dose of an approved COVID-19 vaccine at least 14 days prior to a cruise starting.“We are excited to once again serve our guests from the U.S., and we express our deep gratitude to all national, state and local officials who have worked collaboratively with us, the CDC and our entire industry to make this possible,” Carnival Corp. CEO Arnold Donald said in a statement accompanying the announcement.Thursday’s announcement is welcome news for tourist towns in Southeastern Alaska such as Juneau and Skagway, which haven’t been visited by a cruise ship since the summer of 2019. The towns rely on cruise ships to deliver more than 90% of their visitors in a normal year.Princess on Thursday said the one ship it planned to operate in Alaska starting in July, the 3,560-passenger Majestic Princess, would sail to the Southeastern Alaska towns of Juneau, Skagway and Ketchikan as well as Glacier Bay National Park.Holland America said it would resume Alaska cruises with its 2,106-passenger Nieuw Amsterdam sailing to Juneau, Icy Strait Point, Sitka and Ketchikan. The Holland America trips also will include a visit to Glacier Bay National Park.Carnival said it would resume Alaska cruises with its 2,124-passenger Carnival Miracle sailing to Juneau, Skagway and Ketchikan as well as Tracy Arm Fjord.All of the voyages will be seven nights in length.Assuming all goes according to plan, the lines will offer the Alaska departures through Sept. 26, Oct. 2 and Sept. 14, respectively.Planning a cruise? Start with these stories:The 5 most desirable cabin locations on any cruise shipThe 8 worst cabin locations on any cruise shipA quick guide to the most popular cruise lines21 tips and tricks that will make your cruise go smoothly15 ways cruisers waste money12 best cruises for people who never want to grow upWhat to pack for your first cruise