What an association can and cannot do about it

The distinction that trips up boards: an abatement is a per-property remedy, not a community one. Each owner applies for their own parcel or unit, on their own facts, by the same March 1 deadline. A board cannot file one application on behalf of 100 units.

What a board can do is the part that actually determines whether the applications succeed:

Assemble the comparables. An abatement turns on whether the assessment exceeds market value, or exceeds proportionally what comparable properties bear. In a condominium, the best comparable evidence is the community's own recent arm's-length sales, and the association is the only entity that sees all of them.

Document the private-infrastructure burden. A schedule showing what the association spends per unit per year on road maintenance, plowing, trash, water and wastewater is the factual predicate for a proportionality argument. It is an argument, not a rule — New Hampshire law does not require an assessor to discount for privately borne services — but it cannot be made at all without the numbers.

Tell owners the deadline exists. March 1 is not widely known, it is absolute, and an association that circulates one notice in January does more good than any amount of complaining in June.

The revaluation cycle is the reason these arrive in waves

RSA 75:8-a puts New Hampshire municipalities on a five-year revaluation cycle. That is why a community can go years with nothing happening and then absorb a 94 percent increase at once — the market moved continuously and the assessment did not.

It also means the increase is predictable in timing if not in size. A board that knows its town's revaluation year can put an abatement-deadline reminder on the calendar in advance rather than react to the notices.

The same pattern elsewhere in the state

Rochester is not an outlier. Concord's 2026 revaluation produced a median single-family increase of 62 percent, with the city reporting that manufactured homes and condominiums rose by more than the citywide average.² The city's report to its council: "Because the residential real estate market has been substantially more active than the commercial/industrial market, it is anticipated that the longstanding trend of residential property owners assuming a greater share of the overall tax burden will continue."

Durham's 2025 statistical revaluation put condominiums up an average of 22 percent, matching residential property across all strata, with an abatement deadline of March 1, 2026.

Phil Sletten of the New Hampshire Fiscal Policy Institute, on Concord: "What's happening in Concord is not necessarily unique."

What to watch next

Whether the classes that moved most also appeal most. The Board of Tax and Land Appeals does act on systemic complaints — it ordered a reassessment in Conway after homeowners complained that commercial property was being assessed below the acceptable band, shifting burden onto residential taxpayers — but that is a challenge to the revaluation's methodology, not to an individual assessment, and it is a much heavier lift than an abatement.

For most owners in a New Hampshire common-interest community the practical horizon is narrower: find the notice, check the comparables, file by March 1.