Analyzing 7,203,8127.2M ReviewsFor 20,40220.4K Experts
We graded 8 companies on seven things customers actually report: satisfaction, reliability, workmanship, value, momentum, track record and how owners handle complaints.
From 45,465 Google reviews of 46 top-rated gas contractors nationwide; 8 of them in San Francisco, CA. Updated November 2, 2026.
Pick the job — we re-rank companies by how customers rated that exact job.
Experts Score 0–100Experts Score (0–100)Absolute quality first: recency-weighted star average (≈54%), share of 1–2★ reviews (≈24%), customers’ price verdicts (≈14%), owner replies to critical reviews (≈7%); minus up to 10 points each for complaints flagged in Google review highlights and for a real slide in recent ratings. Hover a company’s score on its page for the full breakdown. and a letter grade per factor (A = top 20% of gas contractors).
| # | Company | ScoreExperts Score (0–100)Absolute quality first: recency-weighted star average (≈54%), share of 1–2★ reviews (≈24%), customers’ price verdicts (≈14%), owner replies to critical reviews (≈7%); minus up to 10 points each for complaints flagged in Google review highlights and for a real slide in recent ratings. Hover a company’s score on its page for the full breakdown. | FactorsFactor grades, in orderSatisfaction (54%): Recency-weighted star average (2-year half-life), shrunk toward the category mean by review volume; the company’s own lifetime average as the prior; absolute: 4.0★ = 0, 5★ = 100.Reliability (24%): How rarely jobs go badly: share of 1–2★ reviews — 60% the last 24 months (or the 20 newest if fewer), 40% all-time; 0% = 100, 15%+ = 0; the category percentile can only raise it.Craft & service (0%): Google review highlights: Quality, Professionalism, Responsiveness, Punctuality — how rarely reviewers flag them as a negative, per review since highlights began; 0% = 100, 5%+ = 0. Subtracted from the score (up to −10), never averaged in — clean highlights are the norm, not a bonus.Value (14%): Customers’ own price verdicts (Great / Reasonable vs Overpriced) and Value highlights; 65% absolute (all “reasonable” ≈ 80, “great” = 100), the category percentile can only raise it.Momentum (0%): Penalises only a real slide: last-12-month average below lifetime (−0.5★ = 0). Still 4.8★+ over the last year, or steady/improving = 100. Subtracted from the score (up to −10), never averaged in.Replies to reviews (7%): How often the owner publicly replies to reviews under 5★ (1–4★). Needs 3+ such reviews, otherwise not counted; 65% absolute (80%+ replied = 100), the category percentile can only raise it.One letter per factor score: A = 80+, B = 60–79, C = 40–59, D = 20–39, F = below 20. | ★Google star rating as shown on Google Maps. | Typical billMedian bill customers of this company reported in their reviews (needs 3+ priced reviews). |
|---|---|---|---|---|---|
| 1 |  Fast Response Plumbing & RooterSan Francisco, CA | A 94How the Experts Score is calculatedEach factor is scored 0–100 on absolute terms (standing in the category can only raise it), then weighted; problems flagged in review highlights or a recent slide in ratings are subtracted:Satisfaction 55%94+51.3Reliability 24%93+22.5Value 14%100+14.1Replies to reviews 7%87+6.2Craft & service penalty94−0.6Experts Score= 94Grade A: A = 80+, B = 60–79, C = 40–59, D = 20–39. Needs 10+ reviews. | AAAAAA | 4.94 | $264 |
| 2 |  1 Backflow PlumbingSan Francisco, CA | A 94How the Experts Score is calculatedEach factor is scored 0–100 on absolute terms (standing in the category can only raise it), then weighted; problems flagged in review highlights or a recent slide in ratings are subtracted:Satisfaction 59%96+56.3Reliability 26%91+23.7Value 15%93+14.2Craft & service penalty99−0.1Experts Score= 94Not enough data for replies to reviews; its weight is shared by the others.Grade A: A = 80+, B = 60–79, C = 40–59, D = 20–39. Needs 10+ reviews. | AAAAA– | 4.97 | $161 |
| 3 |  George Salet Plumbing, Inc.San Francisco, CA | A 94How the Experts Score is calculatedEach factor is scored 0–100 on absolute terms (standing in the category can only raise it), then weighted; problems flagged in review highlights or a recent slide in ratings are subtracted:Satisfaction 55%94+51.3Reliability 24%95+23Value 14%94+13.3Replies to reviews 7%86+6.1Experts Score= 94Grade A: A = 80+, B = 60–79, C = 40–59, D = 20–39. Needs 10+ reviews. | AAAAAA | 4.95 | $881 |
| 4 |  Advanced Plumbing & DrainSan Francisco, CA | A 92How the Experts Score is calculatedEach factor is scored 0–100 on absolute terms (standing in the category can only raise it), then weighted; problems flagged in review highlights or a recent slide in ratings are subtracted:Satisfaction 55%93+50.7Reliability 24%91+22.1Value 14%100+14.1Replies to reviews 7%71+5Craft & service penalty97−0.3Experts Score= 92Grade A: A = 80+, B = 60–79, C = 40–59, D = 20–39. Needs 10+ reviews. | AAAAAB | 4.94 | $305 |
| 5 |  Cabrillo Plumbing, Heating & AirSan Francisco, CA | A 92How the Experts Score is calculatedEach factor is scored 0–100 on absolute terms (standing in the category can only raise it), then weighted; problems flagged in review highlights or a recent slide in ratings are subtracted:Satisfaction 55%92+50.2Reliability 24%92+22.3Value 14%100+14.1Replies to reviews 7%89+6.3Craft & service penalty94−0.6Experts Score= 92Grade A: A = 80+, B = 60–79, C = 40–59, D = 20–39. Needs 10+ reviews. | AAAAAA | 4.92 | $748 |
| 6 |  Heise's PlumbingSan Francisco, CA | A 83How the Experts Score is calculatedEach factor is scored 0–100 on absolute terms (standing in the category can only raise it), then weighted; problems flagged in review highlights or a recent slide in ratings are subtracted:Satisfaction 55%88+48Reliability 24%87+21.1Value 14%72+10.2Replies to reviews 7%61+4.3Craft & service penalty98−0.2Experts Score= 83Grade A: A = 80+, B = 60–79, C = 40–59, D = 20–39. Needs 10+ reviews. | AAABAB | 4.88 | $406 |
| 7 |  Ace Plumbing & Rooter, Inc.San Francisco, CA | A 83How the Experts Score is calculatedEach factor is scored 0–100 on absolute terms (standing in the category can only raise it), then weighted; problems flagged in review highlights or a recent slide in ratings are subtracted:Satisfaction 55%86+46.9Reliability 24%84+20.4Value 14%90+12.7Replies to reviews 7%41+2.9Experts Score= 83Grade A: A = 80+, B = 60–79, C = 40–59, D = 20–39. Needs 10+ reviews. | AAAAAC | 4.89 | $529 |
| 8 |  Magic Plumbing Heating & CoolingSan Francisco, CA | B 71How the Experts Score is calculatedEach factor is scored 0–100 on absolute terms (standing in the category can only raise it), then weighted; problems flagged in review highlights or a recent slide in ratings are subtracted:Satisfaction 55%81+44.2Reliability 24%65+15.8Value 14%100+14.1Replies to reviews 7%34+2.4Craft & service penalty95−0.5Momentum penalty49−5.1Experts Score= 71Grade B: A = 80+, B = 60–79, C = 40–59, D = 20–39. Needs 10+ reviews. | ABAACD | 4.86 | $767 |
What customers paid, from the price Google asks reviewers to report.
| Job | Low25th percentile: 1 in 4 customers paid less than this. | TypicalMedian of the bill customers reported in their Google review (Google asks reviewers for a price range; we use the middle of each range). | High75th percentile: 1 in 4 customers paid more than this. | FairOf customers who rated the price, the share who chose “Great price” or “Reasonable” rather than “Overpriced”. |
|---|---|---|---|---|
| Drain cleaning | $57 | $239 | $393 | 97% |
| HVAC system maintenance | $26 | $78 | $251 | 98% |
| Toilet repair | $124 | $317 | $554 | 94% |
| Plumbing pipe repair | $251 | $506 | $1.4k | 96% |
| Water heater installation | $1.2k | $1.9k | $2.5k | 96% |
| A/C system maintenance | $26 | $83 | $322 | 96% |
| Plumbing leak detection | $57 | $248 | $506 | 93% |
| Faucet repair | $216 | $366 | $655 | 94% |
| Plumbing leak repair | $251 | $454 | $968 | 92% |
| HVAC system repair | $161 | $366 | $882 | 95% |
| Heating system maintenance | $19 | $57 | $195 | 99% |
| Water heater repair | $114 | $353 | $680 | 93% |
How the 8 gas contractors we rated in San Francisco, CA compare, and what customers praise most.
A = score 80+, F = below 20.
Average stars per company.
Share of Google review highlights.
All price verdicts left with reviews.
Share calling it great / reasonable / overpriced.
Satisfaction (54%) — Recency-weighted star average (2-year half-life), shrunk toward the category mean by review volume; the company’s own lifetime average as the prior; absolute: 4.0★ = 0, 5★ = 100.
Reliability (24%) — How rarely jobs go badly: share of 1–2★ reviews — 60% the last 24 months (or the 20 newest if fewer), 40% all-time; 0% = 100, 15%+ = 0; the category percentile can only raise it.
Craft & service (penalty, up to −10) — Google review highlights: Quality, Professionalism, Responsiveness, Punctuality — how rarely reviewers flag them as a negative, per review since highlights began; 0% = 100, 5%+ = 0. Subtracted from the score (up to −10), never averaged in — clean highlights are the norm, not a bonus.
Value (14%) — Customers’ own price verdicts (Great / Reasonable vs Overpriced) and Value highlights; 65% absolute (all “reasonable” ≈ 80, “great” = 100), the category percentile can only raise it.
Momentum (penalty, up to −10) — Penalises only a real slide: last-12-month average below lifetime (−0.5★ = 0). Still 4.8★+ over the last year, or steady/improving = 100. Subtracted from the score (up to −10), never averaged in.
Replies to reviews (7%) — How often the owner publicly replies to reviews under 5★ (1–4★). Needs 3+ such reviews, otherwise not counted; 65% absolute (80%+ replied = 100), the category percentile can only raise it.
The 10 best-rated gas contractors in San Francisco, CA average 4.9★ on Google across 12,393 reviews. Flow Masters Plumbing, Drain and Water Heater has the top rating (5.0★), and Discount Plumbing Rooter Services has the most reviews (3,285). Updated October 29, 2026.
10 companies that meet our bar: rated 4.5★ or higher on Google, with a meaningful review history (12,393 reviews combined) and currently operating. Request a call back and the company will phone you directly.
“Miguel and Daniel were great! They were very professional, and solved the issue with my broken ignitor on my hot water heater right away. Miguel even thought to mention ahead of time that I could purchase and ignitor…” — Google review
“Danny and Carlos were great nothing leaked in the underground drain repair and they cleaned up nicely. Good guys good job👍” — Google review
“Great service. I called in the evening and they sent someone out the next morning. Everyone else I called either couldn’t sent someone for a week or they never called back. The tech was able the figure out the…” — Google review
“My neighbor had called the plumber and I was able to schedule a repair with the gentleman an hour later. They were on time and did a great job. Highly recommended.” — Google review
“On time, professional and friendly tech, knowledgeable, job started, finished and cleaned up in less than an hour. We have used another company for years, their prices went up, service went down and not consistent…” — Google review
“I am so grateful that the Cabrillo team saved my HVAC: special shout out to Justin (the repair technician) and coordinating staff (Gessa, Candice, and Sal). They are so organized and excellent at following up. My…” — Google review
“I had a leaking drain pipe in the wall that needed to be located and fixed. Dylan was great to work with, very professional and courteous. Did a great job replacing an old cast iron section of pipe with new copper.…” — Google review
“Hired for annual backflow prevention testing. He gave us some other suggestions for maintenance of our set-up since we just purchased the house. Easy to book online. He came on-time and the process was seamless.…” — Google review
“Exceptional work with recent installation of a new water heater! Fast, professional, courteous. Fast Response Plumbing & Rooter is our 'go-to' for all plumbing needs. Thank you! Oleg, Val.” — Google review
“We’ve been using George Salet Plumbing for years… today I had an emergency and John was able come over quickly. They are honest, and really know what they are doing. We’ve never been disappointed.” — Google review
We scan Google Maps for gas contractor listings in and around San Francisco, keep only open businesses whose main category matches the service, and require a Google rating of at least 4.5 from at least 20 reviews. Companies are ordered by a confidence-weighted score that balances rating and review volume. We do not accept payment for placement.
Flow Masters Plumbing, Drain and Water Heater has the highest Google rating on our San Francisco list: 5.0 out of 5 from 715 reviews (as of October 29, 2026).
Discount Plumbing Rooter Services has the most Google reviews among the companies listed here: 3,285, with a 4.9★ average.
Only open San Francisco-area businesses whose Google category matches the service, rated at least 4.5★ from at least 20 Google reviews. They are ordered by a confidence-weighted score of rating and review volume. Placement is never paid.
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Analyzing 7,203,8127.2M ReviewsFor 20,40220.4K Experts