The vessel, called the Pineapple, ran into bad weather after departing from Guam on Jan. 6 on a journey to the Philippines and relatives of the crew - four men and a woman - reported them missing Jan. 18.
A Philippine coast guard ship reached the 38-foot (11-meter) catamaran on Sunday after it was spotted by plane the previous day. Rescuers escorted the vessel to the port of Maasin on Leyte Island, where the crew refueled, got their passports stamped and treated themselves to a meal, the coast guard said.
With one of its two rudders damaged, the Pineapple will later be escorted to its original destination on Cebu Island.
"They're all in fine health," coast guard chief Adm. Wilfredo Tamayo said of the crew, including a Filipino-American in the U.S. Air Force. The U.S. Embassy in Manila has declined to release their identities and hometowns.
The U.S. Coast Guard, which said it had spent 63 hours searching for the sailboat, expressed relief that the boat was found but faulted the crew for failing to take proper precautions. The vessel did not carry long-distance communication or emergency distress equipment and did not file a comprehensive float plan, the agency said.
"I'm elated for the family and friends of the Pineapple, but compelled to point out that this voyage was made without taking basic, commonsense precautions," said Capt. Thomas Sparks, U.S. Coast Guard Guam commander.
A Philippine coast guard plane spotted the sailboat Saturday off the southern island of Dinagat, but was not able to confirm its identity until Sunday when the weather cleared, Tamayo said.
A woman aboard the boat was able to contact her husband by cell phone at 1:30 p.m. Sunday - apparently once she came within range of cell phone service - and he called rescuers in Guam to give them the boat's coordinates, the U.S. Coast Guard said in a statement.
"The husband confirmed the vessel ran into bad weather and suffered a rudder and radio casualty. This delayed the Pineapple's voyage but it was never in danger of sinking," the statement said.
Guam, a U.S. territory, is about 1,400 miles (2,290 kilometers) east of Cebu, where heavy rains and rough seas have been reported in recent weeks.
The U.S. Coast Guard had deployed a HC-130 Hercules aircraft, two Navy P-3 Orion planes, two Air Force C-12s and a patrol ship to search an area of 122,600 square nautical miles (317,530 square kilometers) for more than 63 hours, the agency said.
U.S. authorities were informed of the discovery by Philippine authorities and have been in touch with Philippine officials to provide help to the Americans, U.S. Embassy spokeswoman Rebecca Thompson said.
A video taken from a search plane showed four of the Americans on top of the white-hulled catamaran, one apparently waving, as a rubber boat with coast guard personnel approached.
Many Philippine provinces, particularly in the east, have experienced rough seas amid unusually heavy rains since late December. At least 71 people have died and 23 others remain missing from the stormy weather.
The Philippine coast guard rescued 260 of 277 people aboard nearly a dozen boats that sank, overturned or ran into trouble last week due to the inclement weather. Fifteen remain missing while two drowned, the officials said.