High-Value Home Insurance on Mount Desert Island, ME

By Jonathan Merwin, Founder and CEO, Licensed Insurance Advisor. Updated October 31, 2026.

Who insures large and historic homes on Mount Desert Island? Portsmouth Atlantic Insurance is an independent agency licensed in Maine that compares 40+ carriers for summer cottages, shingle-style estates and year-round homes in Bar Harbor, Northeast Harbor, Seal Harbor, Somesville, Southwest Harbor and Tremont. On this island, the right policy starts with three questions: how fire crews reach the house, how much water it can see in a winter storm, and who looks after it from October to May.

Four island settings, four sets of questions

Somes Sound splits the island, and Acadia National Park wraps around much of the interior. Each side of the sound brings different questions for an underwriter.

The causeway, storm tides and getting to the house

Every car, fire engine and contractor’s truck reaches the island over the Route 3 causeway from Trenton. The Hancock County plan, which covers Bar Harbor, Mount Desert, Southwest Harbor and Tremont, ties flooding there to the single tide gauge at Bar Harbor. At a 15.5-foot tide, low spots on the Bar Harbor pier and the island side of the causeway begin to flood. At 17 feet, the waterfronts of Southwest Harbor and Bar Harbor flood, the causeway carries up to 2 feet of water and Route 102 in Tremont takes up to a foot. At 18 feet, the plan expects widespread flooding of island waterfronts and piers, up to 3 feet on the causeway, and the first water on Peabody Drive in Seal Harbor.

The January 2024 storms showed what those numbers look like. National Weather Service reports from January 10 describe water and debris on Route 3 northwest of Bar Harbor, a partial lane closure on the road between Trenton and the island, Seawall Road impassable under large rocks and water, a century-old dock house in Tremont washed into the sea, and boulders and trees on the Otter Cove causeway in the park. Three days later, Shore Road in Manset flooded with water lapping at several structures and Isleford Dock on Little Cranberry Island flooded.

What that means for the policy

We look at how long the house could be unreachable, whether the alarm company and caretaker can get there, and how much additional living expense you would need if a repair waits on contractors who are busy across the whole coast.

Fire: what 1947 still teaches underwriters

The National Park Service history of the 1947 fire is worth reading for anyone who owns a wooded property here. A dry summer and fall left the island with the driest conditions on record by mid-October. The fire started near Hulls Cove on October 17 and burned only 169 acres in its first three days. Then the wind picked up, and on October 23 a dry cold front drove it six miles toward Bar Harbor in less than three hours. In all, 17,188 acres burned, and the fire was not declared fully out until November 14.

Many of the great summer cottages were never rebuilt. Underwriters today still ask the questions that story raises: how far the house is from a staffed fire station, whether there is a hydrant or a reliable water source nearby, how close the woods come to the walls, and what the roof is made of. A cedar shingle roof on a cottage surrounded by spruce and fir draws a closer look than a slate or metal roof with cleared space around it.

Water for fire crews

The Town of Mount Desert’s 2009 comprehensive plan describes two public water systems run by the Mount Desert Water District. Northeast Harbor draws from the Hadlock Ponds, and Seal Harbor from Jordan Pond, and each system has a 500,000-gallon storage tower. The plan says the systems have enough capacity for summer demand, which runs about three times the demand in other months. It also says extending the network to the west side of the island, where most new building was happening, would be prohibitively expensive. In practice, a house in Northeast Harbor village and a house on a private well near Pretty Marsh can look very different to an underwriter, even at the same value.

Rebuilding historic and shingle-style homes

Much of the island’s value sits in houses that would be hard to replace: shingle-style cottages, timber-framed village homes and large estates finished with custom millwork. The 2009 Mount Desert plan lists the Somesville Historic District, about 30 buildings at the head of the sound, on the National Register since 1975, and notes that the Gilman summer home in Northeast Harbor was the town’s first National Register listing in 1966.

In Bar Harbor, the town requires a certificate of appropriateness from the Design Review Board before many exterior changes in the Design Review Overlay District. The town lists windows and doors, siding and roofing, and the demolition or relocation of a historic building among the projects that need one. After a fire or a storm, that review can affect the materials, the design and the time a repair takes.

• Dwelling limit: set from a rebuild estimate for the materials and trades the house actually needs, not from what the house would sell for. Try our replacement cost estimator for a first figure.
• Extended replacement cost: a cushion for when labor and materials are scarce after a storm that hits the whole coast.
• Ordinance or law: pays for code upgrades and required design changes during a rebuild.
• Additional living expense: sized for a long repair on an island, including time for design review.

Our historic home insurance guide covers these coverages in more depth.

Shoreland rules and the waterfront

Maine’s Mandatory Shoreland Zoning Act requires each town to regulate land use within 250 feet of the upland edge of a coastal wetland, which includes all areas affected by tidal action, and within 250 feet of great ponds and rivers. Each town enforces its own ordinance through its code enforcement officer, according to the Maine DEP shoreland zoning page. Among the act’s stated purposes is protecting buildings and land from flooding and erosion.

On Somes Sound, Frenchman Bay or Long Pond, that ordinance can shape how a damaged house, deck, dock or boathouse is rebuilt, which is one more reason to carry enough ordinance or law coverage.

Flood above the federal limit

A homeowners policy does not cover flood. The NFIP limits a house to $250,000 on the structure and $100,000 on belongings, and coverage normally begins 30 days after purchase (FloodSmart). Buying it once a nor’easter is named is usually too late.

Most island estates sit high on ledge, so flood is often a question about specific parts of the property rather than the whole house. A boathouse, a waterfront guest cottage, a garage near the road or mechanical equipment in a lower level can be exposed even when the main floor is well above any storm tide. Where flood makes sense, our NFIP policies are placed with Selective, and we can stack or swap in private and excess flood from Neptune, Beyond Floods, Flow Flood or Aon Edge. Our Maine flood insurance page walks through flood zones and elevation certificates, and you can check a flood zone first.

Wind, nor’easters and the hurricane deductible

Most damage on the island comes from winter nor’easters, which are handled under the ordinary all-peril deductible. Maine Rule 960 limits the period in which a hurricane deductible can apply, and an owner-occupied home’s declarations page has to disclose it (Maine Bureau of Insurance Bulletin 398). Many island homes are seasonal, so we read each carrier’s own wording and show the hurricane deductible in dollars before you choose.

Seasonal homes and the long off-season

Seasonal ownership is the norm in much of the island. The 2009 Mount Desert plan found that more than half of the housing in Northeast Harbor was used seasonally, as was about half of the East Side as a whole, with Seal Harbor at 53% and Pretty Marsh at 58%. Many of those houses are closed from October to May.

Shutting a cottage for the winter invites frozen pipes, ice dams and multi-day outages. Carriers usually ask who checks the house and how often, whether the heat stays on or the plumbing is drained, and which devices are installed. Low-temperature alarms, an automatic water shutoff, remote monitoring and a standby generator all help the file. Weekly summer rentals should be mentioned on day one; renting can shift the policy form and narrow the list of willing carriers. Our Maine second home page and vacant home guide cover those situations.

Carriers we compare for island homes

For a Southwest Harbor waterfront home or a Somesville village house, Hanover can write Maine homes valued up to $2 million and Patriot up to $3 million. Larger cottages and newer custom homes may fit National General or Openly, which can each go to about $5 million. The largest Bar Harbor and Northeast Harbor estates, and homes with fine art, silver, wine or jewelry to schedule, often go to Chubb or Cincinnati. Hagerty handles collector cars. Underwriters differ on water supply, roof type, wood heat, vacancy and outbuildings, and this page on how we choose carriers lays out the factors we weigh.

Boats on a Northeast Harbor or Southwest Harbor mooring need their own Maine boat policy. An umbrella policy is the usual way to add liability limits above a home of this size, and older cars belong on a collector car policy.

What to have ready for a Mount Desert Island quote

• Street address, year built, square footage and any major renovations.
• Whether the house is on public water or a private well, and the distance to the nearest fire station.
• Roof material and age, heating system, chimneys and any wood stoves.
• Alarms, generator, low-temperature sensors and water shutoff devices.
• How the house is used: year-round, seasonal or rented, and who checks it.
• Boathouses, guest cottages, garages and docks.
• Current declarations pages and any loss history.

Related pages: Maine high-value home insurance, Kennebunkport high-value homes, Maine flood insurance, Maine landlord insurance and New Hampshire high-value homes.

Frequently asked questions

Sources

• Hancock County, Maine Hazard Mitigation Plan, 2024 Update, Element B: Risk Assessment (see also the county plan page)
• National Weather Service Caribou, January 10 and 13, 2024 coastal flood reports
• National Park Service, Acadia National Park: Fire of 1947
• Town of Mount Desert Comprehensive Plan Update, adopted May 5, 2009
• Town of Bar Harbor, Design Review Board
• Maine DEP, Mandatory Shoreland Zoning
• Maine Bureau of Insurance, Bulletin 398
• FloodSmart (NFIP), Buy a policy

About Portsmouth Atlantic Insurance

Portsmouth Atlantic Insurance is a family-owned independent agency founded in Portsmouth in 2005 and licensed in 10 states. We compare 40+ carriers, hold an A+ rating with the Better Business Bureau, and are New Hampshire’s highest-rated agency on Google, with 1,000+ Google reviews and over 2,000 testimonials (see our client feedback). Our team brings 200+ years of combined experience. We don’t charge any fees.

We serve Mount Desert Island homeowners from our Portsmouth, NH office by phone at (603) 431-4020, by email at insure@portsmouthatlanticins.com, online and by video, including summer residents who live out of state.