Also helping to reduce the damage, Parma weakened slightly and changed course overnight Friday so that it missed central Luzon and clipped the more sparsely populated and mountainous north.
Still, winds of 108 mph (175 kph) battered towns in at least two provinces and pelted the northeast of the country with downpours that swelled rivers to bursting, toppled power pylons and trees, and cut communication lines to outlying towns, officials said.
Parma was heading northwest toward Taiwan, which declared a storm warning Saturday and began evacuating villages in southern Kaohsiung county, where 700 people were killed in a typhoon in August.
"The typhoon could bring torrential rain and trigger flash flooding, so government agencies should be prepared," Vice Premier Eric Chu was quoted as saying by the government-owned Central News Agency.
In the Philippines' hard-hit Isabela province, one man drowned and another died from exposure to the cold and wet weather, said Lt. Col. Loreto Magundayao of an army division based there.
The National Disaster Coordinating Council said another two people died from the storm in the eastern province of Camarines Sur - one man fell from a roof and a two-year-old boy drowned.
Parma hit the coast mid-afternoon Saturday, and local officials said the true extent of damage would not be known until communications were restored with outlying areas on Sunday or later.
"The damage is quite heavy," Roberto Damian, the police chief of Cagayan province, told ABS-CBN television. "We are clearing highways and roads to reach people calling for rescue."
In Ilagan, Isabela's capital, the swollen Cagayan River rose enough to swamp two bridges, officials said. In the Cagayan city of Tuguegarao, telephone landlines were down and mobile services were intermittent, said Chito Castro, regional director for the Office of Civil Defense.
Ahead of the storm, weather bureau chief Prisco Nilo warned that heavy rain could trigger landslides and flooding, and strong winds could create tidal surges along the eastern coast. None of those conditions were reported by Saturday night.
Manila escaped the worst of the storm. On Sept. 26, Tropical Storm Ketsana caused the worst flooding in four decades, killing at least 288 people and damaging the homes of 3 million.
Rain fell in the city most of Saturday, and stiff gusts of winds blew, but no new flooding or damage was immediately reported.
Even before the storm hit, officials in eastern provinces judged they were no longer in danger and began moving back people who had been evacuated from coastal areas that might have been in the path of the storm.
After devastating parts of Manila, Ketsana went on to hit other Southeast Asian countries, killing 99 in Vietnam, 14 in Cambodia and 16 in Laos.
Parma was part of more than a week of destruction in the Asia-Pacific region that has claimed more than 1,500 lives so far: an earthquake Wednesday in Indonesia; a tsunami Tuesday in the Samoan islands, and Ketsana.
Another typhoon, Melor, was churning in the Philippine Sea, 1,600 miles (2,575 kilometers) to the east, threatening the U.S. territory of the Northern Mariana Islands.
Most businesses there were shut Saturday morning, and residents of the island of Saipan who don't live in concrete homes moved to typhoon shelters, said Charles Reyes, Northern Marianas Gov. Benigno Fitial's press secretary.
Associated Press writers Oliver Teves in Manila and Debby Wu in Taipei, Taiwan, contributed to this report.