FREEPORT — For the first time since Regional School Unit 5 formed in 2009, teachers in Freeport, Durham and Pownal schools are working under one contract that was signed Tuesday afternoon by district and union officials.

The hard-won agreement brings teachers’ salaries in Durham and Pownal schools in line with higher-paid staff members in Freeport. The three-year contract also provides a .6 percent retroactive salary increase for the school year ending June 30, followed by a 1 percent increase in 2012-13 and a 1.75 percent increase in 2013-14.

Negotiators also addressed many other issues – working conditions, employee benefits and grievance procedures, to name a few – as they developed a new agreement for teachers in the three towns.

“Salaries were only part of what we did,” said Nelson Larkins, school board chairman. “The contract is over 50 pages long and we created every single article from scratch.”

The district’s teachers continued to work under separate contracts after RSU 5 formed three years ago. They approved the contact last week by a close 65-56 vote, after reaching a deadlocked 58-58 vote the week before. The school board approved the contract on May 9.

The teachers’ divided vote reflects wide-ranging concerns, from increased health insurance costs for some to changes in personal days, retirement benefits and school starting times for others, said Nancy Drolet, teachers’ union president.

“We’re all giving up a little bit, but it’s the best we could get to as a starting point,” Drolet said. “We need to embrace this contract and move forward. Everyone’s going to be on the same playing field from here on out.”

The contract increases the district’s teacher salary costs by $325,000 the first year, $295,000 the second year and $310,000 the third year, said Kelly Wentworth, RSU 5 finance director. Salary costs will increase a total of $930,000 or 9.9 percent over three years, she said.

Starting annual salary for a teacher with a bachelor’s degree is now $31,236 and will increase to $32,101 in 2013-14, according to the contract. The annual salary for a teacher with a doctorate and 26 years of service is now $64,253 and will increase to $66,031 in 2013-14.

Over time, Larkins said, the school board hopes to move RSU 5 teachers salaries closer to those in neighboring school districts.

Because the contract’s first year is retroactive, district officials and union leaders will be back at the bargaining table in a little more than a year, Drolet said.