Officials feared on Friday the toll could rise as emergency workers tried by air and land to reach communities cut off by flooded rivers or swept away by massive mudslides.
The toll in hardest-hit Guatemala surged to 176 on Friday when rescuers discovered 36 bodies in Solola, 168km west of the capital, President Oscar Berger said.
Hundreds of Guatemalans are missing, he added.
The storm has also killed 67 in El Salvador, 11 in Nicaragua and 22 in Mexico, the authorities in those countries reported.
A soldier carries the body of a
child killed in the storm
Stan slammed ashore as a hurricane in Mexico's state of Veracruz early on Tuesday, but began pounding northern Central America with sheets of rain as early as 1 October.
The 2005 Atlantic hurricane season, which runs from 1 June to 30 November, has been one of the deadliest and most active on record. Stan was the 10th Atlantic hurricane this year.
Hurricane Katrina, which slammed the US Gulf of Mexico coast on 29 August, ravaged New Orleans and coastal areas of Louisiana, Mississippi and Alabama, killing more than 1200 people and becoming the deadliest storm to hit the United States since 1928.