Septic inspection when selling a house in New Hampshire
1 statewide rule and 0 local rules from official sources.
General information, not legal advice. This is our summary of the official rule as we read it. The ordinance or code and the health department decide: confirm with them before you list, sign or close.
Statewide: septic system at sale
Developed waterfront property where any part of the septic system is within 250 feet of the reference line; beyond 250 feet the rule does not apply. A designer must also check systems without state approval or approved before September 1, 1989.
| Question | What the official text says |
|---|---|
| What is required | Buyer engages a NH-licensed septic system evaluator for an evaluation before transfer (a seller's evaluation under 180 days old may be accepted in writing); if the system is within 250 ft of the reference line and not state-approved or approved before 9/1/1989, a permitted septic designer must also check the depth to seasonal high water table Source: web.archive.org via wayback 2025 (gc.nh.gov returned 403) |
| Triggered by | transfer of developed waterfront property using a septic system with any part within 250 ft of the reference line (RSA 483-B:4, XVII) Source: web.archive.org via wayback 2025 (gc.nh.gov returned 403) |
| Deadline | before transfer; designer's determination before transfer Source: web.archive.org via wayback 2025 (gc.nh.gov returned 403) |
| Who arranges it | buyer (may accept a seller-commissioned evaluation completed within 180 days) Source: web.archive.org via wayback 2025 (gc.nh.gov returned 403) |
| Who pays | buyer, at the buyer's expense Source: web.archive.org via wayback 2025 (gc.nh.gov returned 403) |
| How long a report is valid | seller's evaluation accepted if completed within 180 days of transfer (DES may extend up to 180 more days on request) Source: web.archive.org via wayback 2025 (gc.nh.gov returned 403) |
| Exemptions |
Source: web.archive.org via wayback 2025 (gc.nh.gov returned 403) |
| If the system fails | Findings do not prohibit the sale but are disclosed to the buyer; if failure is found, evaluator notifies DES and the local health officer, buyer must replace the system within 180 days of transfer and file the state approval for operation Source: web.archive.org via wayback 2025 (gc.nh.gov returned 403) |
| In force since | September 1, 2024 Source: web.archive.org via wayback 2025 (gc.nh.gov returned 403) |
Checked on November 9, 2026: read in a web-archive copy of the official page (the live site was blocked from our connection).
How the neighbouring states compare
New Hampshire has a statewide rule. Of its 3 neighbouring states, 2 have a statewide rule at sale; a buyer moving across the line may meet a different rule. From our register of official rules:
- Massachusetts: statewide septic system rule at sale.
- Maine: statewide septic system rule at sale.
Other states: all states.