LISBON — A referendum vote to decide the future of a proposed $19 million school budget will take place together with the state primary elections Tuesday.

The ballot will contain three questions: one regarding the proposed school budget, a second which asks whether residents feel the budget is “too low” or “too high,” and a third which asks whether the school budget referendum election should continue in future years.

Question three is required by state law to be on the ballot every three years.

The proposed budget is a 5% increase from the current spending plan of $18 million, and 70% of the increase is due to rising salary and benefits costs, according to Superintendent Richard Green.

Under the proposal, the local share will increase by $317,218, or 4.2%, however the estimated tax rate increase is not yet available.

Included in the budget is an additional third grade teacher, a fifth grade teacher, a middle school literacy specialist, a high school math teacher and a third prekindergarten teacher.

Voting will be held at Lisbon High School from 7 a.m. until 8 p.m.