About 8,000 voters can cast their ballots over four days before Friday's election.
The publication of first results has raised questions among commentators as it might influence the remaining voters.
The Electoral Commissioner Faimalomatumua said they had decided not to 'sleep on the results' and would continue to count and announce the results each day.
189 candidates, including 21 women, are contesting the 50 seats for a five-year term in the legislative assembly.
The ruling Human Rights Protect party has 105 candidates, FAST or Faatuatua i le Atua Samoa party has 52, Tautua Samoa party 14, Samoa First five, the Sovereign Independent Samoa party one, and 12 candidates are independents.
Originally more than 200 candidates were registered but several were forced to withdraw after the court found they failed to meet the eligibility requirements under the Electoral Act.
Campaigning ended on Saturday at midnight.
From Wednesday, a ban on the sale of alcohol will start and last until the morning after the election.