63/100CR Score
Ranked #1 because of its Google rating and review volume: 4.9★ from 156 Google reviews.
Based on 8 of 10 factors; credentials and recency not yet collected.
Best Septic Service Companies in Portsmouth, NH (2026)
25 septic service companies ranked by CR ScoreUpdated 0 paid placements in this rankingHow we rank →
The short answer
- 1
Best overall in Portsmouth: Seacoast Sewer & Drain, Inc., CR Score 63/100; 4.9★ from 156 Google reviews; open 24/7.
- 2
Best for emergencies (open 24/7): Seacoast Septic, posts 24/7 hours; ranked #2 of 25.
- 5
Most-reviewed: Hunts Septic Service, 165 Google reviews at 4.9★, the most of 25 ranked; ranked #5.
Rankings can't be bought. Contractors can't pay to change their rank or score. How we rank
25 Portsmouth septic service companies are ranked here by CR Score, from ten published factors. 8 are open 24/7, 13 open Saturdays and 9 open Sundays, based on posted hours. The median Google rating is 4.9★ across 25 rated businesses.
Top 10 septic service companies in Portsmouth at a glance
| Rank | Business | CR Score | Google rating | Based in | Hours | Best for |
|---|---|---|---|---|---|---|
| 1 | Seacoast Sewer & Drain, Inc. | 63 | 4.9★ (156) | Eliot, 4 mi away | 24/7 | Overall |
| 2 | Seacoast Septic | 62 | 5.0★ (13) | Portsmouth | 24/7 | Emergencies |
| 3 | A-1 Septic Tank Services | 60 | 4.7★ (44) | Sanford, 19 mi away | 24/7 | — |
| 4 | Top Dog Sewer & Drain | 58 | 4.9★ (58) | Chester, 14 mi away | 24/7 | — |
| 5 | Hunts Septic Service | 58 | 4.9★ (165) | Rochester, 22 mi away | — | Most reviews |
| 6 | Roland's Sewer Service | 57 | 4.6★ (9) | Manchester, 14 mi away | 24/7 | — |
| 7 | Chris-Co Construction Services Inc. And Philbrick Septic Tank Services | 56 | 4.6★ (11) | Portsmouth | — | — |
| 8 | Pete's Sewer Services | 56 | 4.8★ (52) | Plaistow, 24 mi away | Sat | — |
| 9 | Septic Designs of NH, LLC | 56 | 5.0★ (103) | Exeter, 11 mi away | — | — |
| 10 | Epping and Exeter Septic Service | 55 | 4.8★ (24) | Exeter, 13 mi away | — | — |
The 25 best septic service companies in Portsmouth, ranked
Ordered by CR Score, a 0–100 score from ten published factors. Paid placement never changes the order.
Based in Portsmouth
62/100CR ScoreRanked #2 because of its Google rating and trade focus: 5.0★ from 13 Google reviews, listed on Google as “Septic system service”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Sanford, 19 mi away
60/100CR ScoreRanked #3 because of its Google rating and trade focus: 4.7★ from 44 Google reviews, listed on Google as “Septic system service”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Chester, 14 mi away
58/100CR ScoreRanked #4 because of its Google rating and review volume: 4.9★ from 58 Google reviews.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Rochester, 22 mi away
58/100CR ScoreRanked #5 because of its Google rating and review volume: 4.9★ from 165 Google reviews, the most in Portsmouth.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Manchester, 14 mi away
57/100CR ScoreRanked #6 because of its Google rating and trade focus: 4.6★ from 9 Google reviews, listed on Google as “Septic system service”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Portsmouth
56/100CR ScoreRanked #7 because of its Google rating and trade focus: 4.6★ from 11 Google reviews, listed on Google as “Septic system service”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Plaistow, 24 mi away
56/100CR ScoreRanked #8 because of its Google rating and trade focus: 4.8★ from 52 Google reviews, listed on Google as “Septic system service”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Exeter, 11 mi away
56/100CR ScoreRanked #9 because of its Google rating and review volume: 5.0★ from 103 Google reviews.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Exeter, 13 mi away
55/100CR ScoreRanked #10 because of its Google rating and trade focus: 4.8★ from 24 Google reviews, listed on Google as “Septic system service”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Sanford, 19 mi away
55/100CR ScoreRanked #11 because of its Google rating and trade focus: 5.0★ from 13 Google reviews, listed on Google as “Septic system service”.
Based on 7 of 10 factors; credentials, recency and availability not yet collected.
Based in Hampstead, 24 mi away
54/100CR ScoreRanked #12 because of its Google rating and trade focus: 4.8★ from 31 Google reviews, listed on Google as “Septic system service”.
Based on 8 of 10 factors; credentials and recency not yet collected.
#13 Sewer Surgeons
Based in Derry, 23 mi away
54/100CR ScoreRanked #13 because of its Google rating and trade focus: 5.0★ from 5 Google reviews, listed on Google as “Septic system service”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Sandown, 22 mi away
54/100CR ScoreRanked #14 because of its Google rating and review volume: 5.0★ from 51 Google reviews.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Barrington, 19 mi away
54/100CR ScoreRanked #15 because of its Google rating and trade focus: 4.8★ from 30 Google reviews, listed on Google as “Septic system service”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Barnstable, 15 mi away
54/100CR ScoreRanked #16 because of its Google rating and review volume: 5.0★ from 25 Google reviews.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Dover, 10 mi away
53/100CR ScoreRanked #17 because of its Google rating and trade focus: 5.0★ from 8 Google reviews, listed on Google as “Septic system service”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Chester, 12 mi away
53/100CR ScoreRanked #18 because of its Google rating and review volume: 4.9★ from 58 Google reviews.
Based on 8 of 10 factors; credentials and recency not yet collected.
#19 A Sewer Services
Based in Amesbury, 17 mi away
51/100CR ScoreRanked #19 because of its Google rating and trade focus: 4.7★ from 17 Google reviews, listed on Google as “Plumber”.
Based on 7 of 10 factors; credentials, recency and availability not yet collected.
Based in Dover, 11 mi away
50/100CR ScoreRanked #20 because of its Google rating and review volume: 4.0★ from 12 Google reviews.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Exeter, 10 mi away
50/100CR ScoreRanked #21 because of its Google rating and review volume: 4.6★ from 37 Google reviews.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Chester, 12 mi away
47/100CR ScoreRanked #22 because of its Google rating and trade focus: 4.6★ from 9 Google reviews, listed on Google as “Demolition contractor”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Amesbury, 23 mi away
45/100CR ScoreRanked #23 because of its Google rating and trade focus: 5.0★ from 5 Google reviews, listed on Google as “General contractor”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Plaistow, 23 mi away
44/100CR ScoreRanked #24 because of its Google rating and trade focus: 5.0★ from 8 Google reviews, listed on Google as “Air compressor repair service”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Biddeford, 24 mi away
42/100CR ScoreRanked #25 because of its Google rating and trade focus: 5.0★ from 4 Google reviews, listed on Google as “Contractor”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Also serving Portsmouth
15 more septic service companies within 25 mi that we can't rank yet: too few reviews, or a trade we couldn't confirm. Listed A to Z.
| Business | Google rating | Distance |
|---|---|---|
| Abbott Bros Inc | 5.0★ (1) | 4 mi |
| AR Septic Solutions & Excavation | 5.0★ (2) | 21 mi |
| Day's Excavation, LLC | 5.0★ (2) | 21 mi |
| Dependable Construction Company Inc | 25 mi | |
| Farrell Contracting Services, LLC | 5.0★ (2) | 15 mi |
| Hayden Excavating Inc. | 5.0★ (1) | 18 mi |
| JDL Excavation | 23 mi | |
| JW Landscape Construction | 5.0★ (1) | 7 mi |
| N P Giroux Excavating LLC | 4.0★ (1) | 20 mi |
| New Hampshire Septic Systems Installations | 25 mi | |
| NH Septic Services | 21 mi | |
| Olofson Landworks LLC | 17 mi | |
| Pagoda Vent Company | 4 mi | |
| QUIRK Real Estate Sales, Development and Construction | 3.0★ (2) | 24 mi |
| Richard Genest Inc | 22 mi |
How we ranked Portsmouth septic service companies
We scored 25 Portsmouth septic service companies on ten factors, weighted as shown. A business is ranked when its trade is confirmed and it has 3 or more Google reviews or a claimed profile. A business with no Google reviews scores zero on rating, review volume and recency. Other unknown factors are left out, not counted as zero. Scores last refreshed November 3, 2026.
Paid placement never changes a rank or score. Featured businesses are paid, labelled, limited to 3 and shown above the ranking, outside it.
| Factor | Weight | Computed from | In Portsmouth data |
|---|---|---|---|
| Reputation | 25% | Google star rating, adjusted for how many reviews back it | Measured |
| Credentials | 15% | Active state license, bond and workers’ comp on file | Not yet collected |
| Review volume | 10% | Number of Google reviews, compared with the most-reviewed business on the list | Measured |
| Recency | 5% | Share of reviews from the last 12 months | Not yet collected |
| Availability | 5% | Weekly open hours, Saturday, Sunday, 24/7 or same-day | Measured |
| Trade focus | 10% | How clearly the business does this trade (its Google category and name) | Measured |
| Proximity | 5% | Based in the city scores highest, less the farther away it is | Measured |
| Claimed profile | 10% | The business has claimed its ContractorsRanked profile (free or paid earn the same) | Measured |
| Partnered | 5% | The business links to ContractorsRanked from its own website with our badge, checked periodically | Measured |
| ContractorsRanked reviews | 10% | Verified customer reviews collected by ContractorsRanked: their rating and how many there are | Measured |
Septic service companies in Portsmouth: frequently asked questions
Who is the best septic service company in Portsmouth?
By CR Score, the highest-ranked septic service company in Portsmouth, NH is Seacoast Sewer & Drain, Inc. with a CR Score of 63/100. It has 4.9★ from 156 Google reviews. It is open 24/7. Seacoast Septic (#2) and A-1 Septic Tank Services (#3) follow. We ranked 25 septic service companies on ten factors, last updated November 3, 2026.
How many septic service companies are there in Portsmouth?
ContractorsRanked ranks 25 septic service companies serving Portsmouth, NH. 2 of them are based in Portsmouth; the rest serve it from nearby towns. Another 15 within 25 mi are listed but not ranked yet. Counts are as of November 2026.
Which septic service companies in Portsmouth are open 24/7?
8 ranked septic service companies in Portsmouth post 24/7 hours. The highest-ranked are Seacoast Sewer & Drain, Inc. (#1), Seacoast Septic (#2) and A-1 Septic Tank Services (#3). Hours come from each business's Google listing as of November 2026, so call to confirm.
Which septic service companies in Portsmouth work on weekends?
13 of 25 ranked septic service companies post Saturday hours and 9 post Sunday hours. The highest-ranked open Saturdays are Seacoast Sewer & Drain, Inc. (#1), Seacoast Septic (#2) and A-1 Septic Tank Services (#3). Posted hours are office hours; crews may book weekend jobs separately.
What Google rating do Portsmouth septic service companies have?
The median Google rating among 25 rated septic service companies in Portsmouth is 4.9★, with a median of 24 reviews. Hunts Septic Service has the most, 165 reviews, and ranks #5. We adjust ratings for review count, so a few five-star reviews cannot top the list.
How does ContractorsRanked rank septic service companies?
Each septic service company gets a 0–100 CR Score from ten published factors, led by reputation (25%), credentials (15%), review volume (10%) and trade focus (10%). A business with no Google reviews scores zero on rating, review volume and recency; other factors we cannot measure are left out. Only businesses with a confirmed trade and 3 or more reviews, or a claimed profile, are ranked.
Do septic service companies outside Portsmouth count in this ranking?
Yes, if they are within 25 mi of the Portsmouth city center, our service radius for septic service companies. Each listing shows where the business is based and how far away it is. Proximity is 5% of the CR Score, so a nearby business gets a small edge.
Can septic service companies pay to rank higher on ContractorsRanked?
No. The CR Score never reads payment status, and this ranking has 0 paid placements. Up to 3 Featured businesses may appear above the list, labelled Featured and showing their honest rank.
Update log for Portsmouth
- November 2026: CR Scores recalculated for 25 septic service companies serving Portsmouth.
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