When annual town meetings convene in April and May, voters in the six Island towns will collectively take up nearly $133 million in operating budgets for 2020. The budgets cover everything from town moderator salaries (highest in West Tisbury at $370) to schools, public safety services, road maintenance and libraries. And across all towns there is at least one trend: growth.

In 2015, the six town budgets totalled about $107 million. Since then, every municipal budget has climbed.

Costs for education, public safety and general government administration are all on the rise. Town administrators and finance directors cite changing state requirements, liability for retirement plans, salary increases, and health benefits as a few of the factors contributing to that growth. They also note that regional assessments, not entirely within their control, greatly affect town budgets.

For the coming fiscal year, Edgartown has the largest proposed operating budget on the Island, topping out at $38.17 million. Oak Bluffs comes in second at $31.12 million, though differences in the kinds of expenses towns choose to present as warrant articles make for imperfect operating budget comparisons between towns.

Aquinnah’s proposed budget numbers are not available yet because the annual town meeting is later than other towns, but town administrator Jeffrey Madison estimated that the operating budget will come in around $5.39 million, the smallest on the Island.

In all towns, educational costs figure prominently in budgets for the fiscal year that begins July 1. Islandwide, towns will be assessed about $56 million for public education, or 42 percent of overall budgets, with $19.30 million going toward the regional high school budget. Elementary school assessments total some $36.40 million.

“I joke that the town is an educational institution that provides other services,” said Tisbury finance director Jon Snyder. “That’s been true for a long time.” Regional high school costs are divided using a statutory formula that sets a minimum contribution from each town and then takes into account enrollment numbers. Tisbury will be spending the large st share on the regional high school in 2020: $5.30 million, followed by Oak Bluffs at $5.12 million according to numbers provided by the school business administrator, Amy Tierney.

Ms. Tierney said in the lower schools, Oak Bluffs has the highest enrollment, while lower schools in Edgartown and West Tisbury get the most funding. The towns pay the Charter School for each student in the lower grades, and funding for high school students at the charter school comes out of the regional high school budget.

Per pupil spending is high on Martha’s Vineyard, Ms. Tierney noted, adding that it is unusual to have so many schools in such a limited geographic area.

“If we were 90 square miles in the middle of the state, we wouldn’t be running six schools,” she said. “Our inefficiencies of not being regional cause higher per pupil costs.”

She said rising salaries, building maintenance and health insurance costs have contributed to growth in Island schools’ budgets.

In West Tisbury, more than half the town budget is set to go toward education for the up-Island regional school district and the regional high school. The up-Island regional district includes the three up-Island towns and two schools: the Chilmark and West Tisbury Schools.

“That’s just the nature of the beast,” said West Tisbury town accountant Bruce Stone, speaking about education spending. He said the town avoided a Proposition 2 1/2 override this year partially due to a decrease in the number of West Tisbury students attending the regional high school. “By the luck of the fact that we have a large drop-off in students in the high school, that line item went down a couple hundred thousand dollars,” he said.

Oak Bluffs town administrator Robert Whritenour said his town will spend more on the elementary school this year, although the town has also avoided the need for an override.

“We’ve had enrollment growth, we’ve had growth in the number of students who are English language learning, and there’s just a requirement to have more resources,” Mr. Whritenour said. “It’s something we’re trying to stay on top of.”

Aquinnah will likely require an override due to increased education costs, Mr. Madison said.

“It’s a once again a difficult situation that we find ourselves in . . . the override is attributable partially to increased school enrollment in both the high school and the up-Island district,” he said.

Most Island towns are also seeing a continued rise in public safety costs.

In Edgartown, which is also asking voters for an override this year, the total for police, fire and EMS has increased by a compound annual growth rate of 3.83 per cent in the last five years based on budgets provided by the town administrator.

“With police, it has been contractual obligations with their collective bargaining unit,” said Edgartown town administrator James Hagerty, speaking about the increases.

The fire department budget has seen a compound annual growth rate of 5.65 per cent between 2016 and 2020. Mr. Hagerty attributed the growth to staffing challenges and increased call volume.

“It’s been the trouble retaining volunteer firefighters. It’s happening across the northeast. How do we retain people and keep our [insurance service office] ratings,” he said.

In Tisbury police, fire and EMS costs have seen a compound annual growth rate of 5.85 per cent since 2016 based on budgets provided by finance director Mr. Snyder. He said police salaries have contributed to the increase, though the department has not grown.

“The department itself has not expanded, so I think if we looked hard at it, it would almost all be in salaries and overtime,” Mr. Snyder said. He also said new state requirements have contributed to a significant expansion in the town ambulance services department.

“We provide a higher level of service than we did five years ago, which is partly because there are higher requirements placed on the service now than there used to be,” Mr. Snyder said. He said salaries are a factor too.

“We’re in a tight market for paramedics and EMTs, so there’s been a lot of salary competition in the towns here and on the Cape. We have a couple of professionals who [commute] to the Island to do shifts here. We have to reach far, and the cost is commensurate.”

Tri-town ambulance services chief Ben Retmeir said the same factors explain significant increases in up-Island towns.

“There are certain things the state says we have to have that we love to say are unfunded state mandates,” he said.

Finance directors noted that much of the money in town budgets pays for the people who work for the towns: their salaries, health insurance, and retirement benefits. Mr. Snyder estimated 75 per cent of the town budget goes to salaries and benefits.

“Most employees get a step increase each year and a modest cost of living increase each year,” he said.

In Oak Bluffs, Mr. Whritenour said modest salary and benefit changes were factors in avoiding a budget override this year.

“With a combination of the slightly slower growth of the regional high school and health insurance not growing as fast, and cost of living adjustments, keeping a handle on those, we’ve made a very conscious effort . . . to keep the budget increases as low as possible,” Mr. Whritenour said.

Towns and regional entities are also facing the looming costs of covering future retirement benefits for employees when they stop working. The so-called OPEB (other post-employment benefits) liability numbers are in the millions for every town.

“That’s a big liability and the town has that facing it,” Mr. Whritenour said.

West Tisbury town accountant Mr. Stone estimated the town will spend $1 million next year to pay down OPEB liability for town and regional employees.

“It’s a good thing. You can’t put it off any longer, but it has an impact,” he said.

Reflecting on the budgeting process, Aquinnah town administrator Mr. Madison listed a litany of costs beyond town control. “Things like the tri-town ambulance, the county budget, the schools, the refuse district, OPEB, which everyone is contributing to, insurance . . . ” he said.

Last week, the county advisory committee, made up of selectmen from each town in Dukes County, approved a $1.75 million county budget, about half of which comes from the towns.

Mr. Snyder noted that while all six towns work together to pay for some services, their budgets vary as much as the towns do. Tisbury, for example, serves as a primary ferry port year-round, while West Tisbury has no harbor or even a town sewer system. In Edgartown, some annual expenses, like the Fourth of July fireworks display, are presented as warrant articles rather than line items in the operating budget. Towns also vary widely in numbers of children enrolled in school.

“We call this six Islands connected by land,” Mr. Snyder said. “There really are six dramatically different towns on the Island; different degrees of wealth, different tax rates. It’s hard to compare towns to one another when they are different in so many ways.”