New Hampshire FSBO Disclosure Requirements (2026)
New Hampshire's mandatory disclosure is narrower than most states — it focuses specifically on hazardous conditions (lead paint, radon, arsenic in water, UFFI). However, common law obligations require disclosure of all known material defects. Arsenic in well water (a distinctive NH issue), radon from granite bedrock, underground oil tanks, and the Massachusetts border commuter context define the NH FSBO landscape.
New Hampshire Disclosure Framework
RSA 477:4-c requires the Residential Disclosure of Hazardous Materials and Conditions. This form is more limited than most state property disclosure forms — it covers specific hazardous conditions rather than general property defects.
However: NH common law requires sellers to disclose all known material defects, even if not specifically listed on the mandatory form. This means you should disclose all significant known conditions about your property's condition, not just the items on the mandatory form.
Arsenic in Well Water — NH's Distinctive Issue
New Hampshire has one of the highest naturally occurring concentrations of arsenic in groundwater of any US state. The state's crystalline bedrock geology (granite) releases arsenic into some aquifers, particularly in the southern and central NH Seacoast region, southern NH, and the Concord/Merrimack Valley area.
NH DES data: Approximately 20% of private wells tested in high-risk areas exceed the EPA's MCL (Maximum Contaminant Level) of 10 ppb for arsenic.
For any property with private well water:
Radon from New Hampshire's Granite Bedrock
New Hampshire's granite geology produces significant radon throughout the state. The EPA designates NH counties in Zone 1 (highest radon risk) and Zone 2 (moderate). Southern NH granite zones — Merrimack, Hillsborough, Rockingham counties — have elevated risk.
Radon disclosure: NH's mandatory form specifically asks about radon. Disclose any testing results. NH buyers routinely include radon contingencies in purchase agreements.
Underground Heating Oil Tanks
New Hampshire's harsh winters create one of the highest percentages of fuel oil home heating of any US state. Pre-1980s homes almost universally had underground oil tanks before conversion to natural gas or propane. USTs rust and leak, creating soil contamination.
NH DES Underground Storage Tank Bureau: Check records at des.nh.gov. Disclose any UST existence, status (active/abandoned/removed), and any known contamination.
Lead Paint in NH's Mill Town Housing
Manchester's Amoskeag Mills (once the world's largest textile manufacturing complex), Nashua, and smaller NH mill towns have dense pre-1940 housing stock built for mill workers. Lead paint is pervasive in these neighborhoods. Federal disclosure required for pre-1978 homes.
Well and Septic in Rural NH
Most NH towns outside Manchester, Nashua, Concord, and a few other municipal service areas use private wells and on-site septic. NH DES regulates both. Septic system age, pump-out history, and any alterations are material disclosures.
NH Transfer Tax
$0.75 per $100 (0.75%) total, split equally. Seller pays $0.375/$100. On a $435,000 sale: seller pays approximately $1,631.