The IOC Executive Board decided on the recommendation during a meeting earlier on Thursday and this will now be ratified by the IOC session in the next few days.
IOC Vice President Juan Antonio Samaranch praised the three cities that made it to the next phase, saying they had what it took to host "a wonderful" event.
He said the Italian bid, which at one point included Torino before the city pulled out, was still good enough with two locations, even though specific questions of financing have not been settled yet.
"At this stage we have a very solid (Italian) project. Milan and Cortina are presenting a very interesting, attractive project," Samaranch, who heads the review of the 2026 bidders, told reporters.
"We understand that the government in Rome is fully supportive of the project. Of course we have details to discuss on financing."
CALGARY SCORES
Calgary won points for what Samaranch, son of the late former IOC President, said was more than 80 percent of venues already in place.
The Canadian city that hosted the 1988 Winter Games also scored with its overall infrastructure, as did the Swedish capital.
The concept for the Turkish city, however, showed shortcomings in several issues, including transportation, telecommunications and airport infrastructure, Samaranch said.
The three cities are the last of initially seven candidates with Swiss city Sion, Japan's Sapporo and Graz in Austria pulling out in recent months, scared off by the cost and size as well as local opposition to the big event.
Calgary has set a non-binding plebiscite on the Games for Nov. 13.
Italian Olympic Committee President Giovanni Malago told reporters: "We were very happy in hearing the words of... Vice President Samaranch on our candidature. This is a very good start for us."
Italy twice launched bids with Rome for the 2020 and the 2024 Summer Games before pulling out midway through bidding.
The IOC's changes to the bidding process in recent years, making it shorter and cheaper for cities, have failed to stop some potential hosts walking away during the candidacy process.
The IOC will elect the winning bid in September 2019 but Thursday's decision means that session, which was to be held in Milan, will move to Lausanne to avoid a conflict of interest as the Italian city is now officially a candidate for the 2026 Games.
(Reporting by Karolos Grohmann; Editing by Martyn Herman and Ken Ferris)
