ADU Rental Income in Maine & NH: Real Numbers From Real Builds

What an ADU actually rents for in Maine and New Hampshire

These are the ranges we see from real owners across southern Maine and the NH Lakes Region — not projections. Rent tracks three things: where the lot sits, how big and well-laid-out the unit is, and whether you rent it year-round or seasonally.

Long-term monthly rent by size

384 sq ft studio — our Bean model:

• Sanford / inland York County: $1,100–$1,400
• Wells / Kennebunk coastal corridor: $1,400–$1,800
• NH Lakes Region (Wolfeboro, Ossipee, Wakefield): $1,200–$1,600

600 sq ft 1-bed — our Newfield model:

• Sanford / inland: $1,400–$1,750
• Wells / Kennebunk coast: $1,800–$2,300
• Lakes Region: $1,500–$1,950

800–900 sq ft 2-bed — our Spruce and Washington models:

• Sanford / inland: $1,800–$2,200
• Wells / Kennebunk coast: $2,300–$2,900
• Lakes Region: $1,900–$2,450

A second bedroom is the single biggest rent multiplier. Moving from the 600 sq ft Newfield to the 882 sq ft Spruce typically adds $400–$700/mo in the same town, because you shift out of the studio and young-professional pool into the small-family and traveling-nurse pool.

Vacation-rental (STR) income

Furnished short-term nightly rates run far higher but swing hard with the calendar:

• Coastal 1-bed (Wells, Kennebunk, Ogunquit-adjacent): peak summer $250–$425/night, shoulder $150–$225, winter $110–$160.
• Lakes Region near water: peak $200–$350/night in July and August, much softer November through April.

A well-run coastal 1-bed STR often books 14–20 peak weeks plus scattered shoulder nights and grosses $28,000–$45,000/year — but you carry cleaning, furnishing, platform fees, and Maine's 9% lodging tax, and you absorb vacancy risk in the off-season. Always check the town first: short-term rental rules vary a lot from town to town (see where vacation-rental ADUs work best).

What drives the spread

• Location. The same Newfield model rents for $500+ more per month on the Wells side of Route 1 than in inland Sanford.
• Finish level. Our Bentley-grade premium package commands top-of-range rent and photographs better for STR listings.
• Layout. A true separate bedroom, in-unit laundry, and a full kitchen move you up a tenant tier.
• Seasonality. Long-term rent is steady; STR income in this region is front-loaded into 10–14 summer weeks.

Rough ROI and payback

Take the Newfield at a turn-key price around $179,000, rented long-term at $1,700/mo:

• Gross rent: about $20,400/year
• Net after property tax, insurance, and maintenance (roughly 20%): about $16,300/year
• Simple payback on the build cost: roughly 11 years — before counting the value the ADU adds to your property.

Run that same unit as a coastal STR and gross income can double, pulling the simple payback toward 6–8 years — at the cost of more management and off-season vacancy. Either way, an ADU on land you already own is one of the few improvements that both throws off monthly cash flow and lifts resale value.

See your numbers

Every lot is different. Use our instant pricing calculator to get a real turn-key number for the model you would rent, or book a free build consult and we will map likely rent against build cost for your specific town.

Rental figures above are general market ranges, not guaranteed income.