FAIRFIELD — Town officials are pushing to correct a funding discrepancy with Benton that they say has left them paying more than their share toward a joint fire budget.

The two towns operate a joint fire and rescue department that covers emergency calls for both Fairfield and Benton residents. Both towns fund the department’s annual budget, but their agreement, last updated in 2014, says Benton’s share can’t increase by more than 5% each year.

With rising staffing costs and talks of expanding the department, Fairfield officials say it isn’t enough.

Councilors from both towns met around a table at the Fairfield Community Center last Wednesday night to discuss Fairfield’s proposal. The change would base Benton’s portion of the fire budget on the town’s percentage of calls averaged over the last five fiscal years, with no cap on increases.

Benton has accounted for about 23% of the department’s calls in the last five years, but the town is funding 18% of this year’s budget because of the cap.

The new proposal would tack on $164,565 to Benton’s bill for this year, in addition to the $273,654 owed under the current agreement.

Fairfield officials drafted an updated agreement to be discussed with Benton officials Wednesday night. If the new agreement is approved by both towns, Fairfield would send Benton a bill for the amount that has been underfunded, Michelle Flewelling, Fairfield town manager, told Benton councilors last week.

“What Benton does with that and how they choose to put that forward to the town of Fairfield is up to you,” Flewelling said.

Flewelling said the discrepancy has grown bigger over the last few years as the department’s budget has increased at a faster rate due to COVID-19 and increases in staffing costs.

Benton Selectwoman Robyn Cyr said the town could rely on financing from its tax increment financing district, which helps Maine municipalities fund projects and keep taxes steady, to fund the payment.

The towns said they would meet again by the end of the year to discuss the agreement further. Councilors from both towns expressed interest in building trust.

“We like our partnership with Benton, we’re in no way looking to hamstring anybody,” Fairfield Chairman Tim Martin said Wednesday. “We’d like to keep this agreement rolling.”

Councilors also discussed the fire department’s future with Delta Ambulance, a nonprofit ambulance service that provides transport services to 13 towns in Kennebec, Somerset and Lincoln counties and has struggled financially in recent years, leading to service fees for municipalities that will rise to at least $55 per capita this year.

Flewelling said she is looking for direction from both councils on whether the joint department should considering operating its own transport service, which would allow them to skirt Delta’s service fees and receive revenue from patient insurance billing.

Councilors from both towns requested to see more data before a decision is made.