VASSALBORO — Town residents are asked to vote today on a $6.6 million school budget that was mistakenly left off the primary election ballot two weeks ago.

Town and school officials say they want to make sure voters are aware of the special election because of a town ordinance that requires at least 125 people to vote for it to be a valid election.

There were 542 municipal ballots cast at the June 12 primary election, which included a selectman’s race and one school committee seat, according to results provided by the town.

Polls will be open at the town office until 8 p.m. today.

Vassalboro is part of Alternative Organizational Structure 92, which includes Waterville and Winslow. Voters in each municipality approve or reject school budgets in separate votes.

At the annual town meeting on June 11, there were few questions about the school budget, which is lower than the current spending plan but will result in a tax increase because of less state funding. It’s estimated the budget will increase taxes by $1 per $1,000 of property valuation, which will change the rate from $10 to $11.

Superintendent Eric Haley said the town is getting $467,146 less in state funding, which accounts for the need to increase taxes.