480 HVAC contractors ranked by CR ScoreUpdated 0 paid placements in this rankingHow we rank →
Best overall in Longmont: M and M Heating, Cooling, Plumbing and Electrical, CR Score 67/100; 4.9★ from 3,075 Google reviews; open 24/7.
Best for emergencies (open 24/7): Welzig Heating, Air, Plumbing & Electric, posts 24/7 hours; ranked #2 of 480.
Most-reviewed: Lion Home Service, 5,912 Google reviews at 4.7★, the most of 480 ranked; ranked #26.
Rankings can't be bought. Contractors can't pay to change their rank or score. How we rank
480 Longmont HVAC contractors are ranked here by CR Score, from ten published factors. 187 are open 24/7, 304 open Saturdays and 255 open Sundays, based on posted hours. The median Google rating is 4.8★ across 480 rated businesses.
| Rank | Business | CR Score | Google rating | Based in | Hours | Best for |
|---|---|---|---|---|---|---|
| 1 | M and M Heating, Cooling, Plumbing and Electrical | 67 | 4.9★ (3,075) | Longmont | 24/7 | Overall |
| 2 | Welzig Heating, Air, Plumbing & Electric | 66 | 4.9★ (1,269) | Longmont | 24/7 | Emergencies |
| 3 | Blue Valley Heating & Cooling | 65 | 4.8★ (1,093) | Longmont | 24/7 | — |
| 4 | TNT Home Services - Longmont | 65 | 4.8★ (865) | Longmont | 24/7 | — |
| 5 | Colorado's Finest Heating and Air Conditioning | 63 | 4.9★ (205) | Longmont | 24/7 | — |
| 6 | Cooper Heating & Cooling | 63 | 4.8★ (4,647) | Broomfield, 18 mi away | 24/7 | — |
| 7 | DNI Heating, AC, Refrigeration, Plumbing & Electrical | 63 | 4.8★ (626) | Berthoud, 6 mi away | 24/7 | — |
| 8 | Jim Needham Heating Cooling Plumbing and Drain | 62 | 4.9★ (5,597) | Thornton, 23 mi away | 24/7 | — |
| 9 | Limelight Services | 62 | 5.0★ (1,508) | Johnstown, 18 mi away | 24/7 | — |
| 10 | Your Comfort Heating & Cooling | 62 | 5.0★ (87) | Longmont | 24/7 | — |
Ordered by CR Score, a 0–100 score from ten published factors. Paid placement never changes the order.
Scores below: based on 8 of 10 factors; credentials and recency not yet collected. Hatched segments mark factors we don't have yet.
Ranked #1 because of its Google rating and trade focus: 4.9★ from 3,075 Google reviews, listed on Google as “HVAC contractor”.
Based in Longmont
Ranked #2 because of its Google rating and trade focus: 4.9★ from 1,269 Google reviews, listed on Google as “HVAC contractor”.
Based in Longmont
Ranked #3 because of its Google rating and trade focus: 4.8★ from 1,093 Google reviews, listed on Google as “HVAC contractor”.
Based in Longmont
Ranked #4 because of its Google rating and trade focus: 4.8★ from 865 Google reviews, listed on Google as “HVAC contractor”.
Based in Longmont
Ranked #5 because of its Google rating and trade focus: 4.9★ from 205 Google reviews, listed on Google as “HVAC contractor”.
Based in Broomfield, 18 mi away
Ranked #6 because of its Google rating and trade focus: 4.8★ from 4,647 Google reviews, listed on Google as “HVAC contractor”.
Based in Berthoud, 6 mi away
Ranked #7 because of its Google rating and trade focus: 4.8★ from 626 Google reviews, listed on Google as “HVAC contractor”.
Based in Thornton, 23 mi away
Ranked #8 because of its Google rating and trade focus: 4.9★ from 5,597 Google reviews, listed on Google as “HVAC contractor”.
Based in Johnstown, 18 mi away
Ranked #9 because of its Google rating and trade focus: 5.0★ from 1,508 Google reviews, listed on Google as “HVAC contractor”.
Based in Longmont
Ranked #10 because of its Google rating and trade focus: 5.0★ from 87 Google reviews, listed on Google as “Air conditioning contractor”.
Based in Firestone, 9 mi away
Ranked #11 because of its Google rating and trade focus: 4.8★ from 710 Google reviews, listed on Google as “HVAC contractor”.
Based in Berthoud, 14 mi away
Ranked #12 because of its Google rating and trade focus: 4.8★ from 1,518 Google reviews, listed on Google as “Heating contractor”.
Based in Frederick, 8 mi away
Ranked #13 because of its Google rating and trade focus: 5.0★ from 244 Google reviews, listed on Google as “HVAC contractor”.
Based in Longmont
Ranked #14 because of its Google rating and trade focus: 4.9★ from 724 Google reviews, listed on Google as “HVAC contractor”.
Based in Loveland, 18 mi away
Ranked #15 because of its Google rating and trade focus: 4.8★ from 2,466 Google reviews, listed on Google as “HVAC contractor”.
Based in Frederick, 10 mi away
Ranked #16 because of its Google rating and trade focus: 5.0★ from 266 Google reviews, listed on Google as “HVAC contractor”.
Based in Loveland, 19 mi away
Ranked #17 because of its Google rating and trade focus: 4.8★ from 2,777 Google reviews, listed on Google as “HVAC contractor”.
Based in Longmont
Ranked #18 because of its Google rating and trade focus: 4.9★ from 61 Google reviews, listed on Google as “HVAC contractor”.
Based in Longmont
Ranked #19 because of its Google rating and trade focus: 5.0★ from 914 Google reviews, listed on Google as “HVAC contractor”.
Based in Longmont
Ranked #20 because of its Google rating and trade focus: 4.9★ from 58 Google reviews, listed on Google as “HVAC contractor”.
Based in Brighton, 5 mi away
Ranked #21 because of its Google rating and trade focus: 5.0★ from 94 Google reviews, listed on Google as “HVAC contractor”.
Based in Boulder, 12 mi away
Ranked #22 because of its Google rating and trade focus: 4.8★ from 607 Google reviews, listed on Google as “HVAC contractor”.
Based in Longmont
Ranked #23 because of its Google rating and trade focus: 4.8★ from 64 Google reviews, listed on Google as “HVAC contractor”.
Based in Longmont
Ranked #24 because of its Google rating and trade focus: 4.8★ from 57 Google reviews, listed on Google as “HVAC contractor”.
Based in Thornton, 18 mi away
Ranked #25 because of its Google rating and trade focus: 4.9★ from 893 Google reviews, listed on Google as “HVAC contractor”.
#1 to #25 are shown in full above. Here are #26 to #50, in CR Score order; each links to its profile. We publish the top 50 of 480 ranked HVAC contractors here; the rest are on their profiles.
20 more HVAC contractors 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 |
|---|---|---|
| 287 plumbing llc | 5.0★ (9) | In Longmont |
| All Pro Plumbing And Heating | In Longmont | |
| Allen Service | 4.7★ (1,589) | 24 mi |
| Armendariz Heating and Cooling, Inc. | In Longmont | |
| Bliss Water Heater & Boiler Repair Service | 4.8★ (72) | In Longmont |
| Economy Repairs of Colorado | 5.0★ (7) | In Longmont |
| EssentialelementsmechanicalLLC | In Longmont | |
| Fix-it 24/7 Plumbing, Heating, Air & Electric | 4.7★ (723) | 21 mi |
| Full Spectrum HVAC Repair | 4.8★ (69) | 9 mi |
| IES Residential | In Longmont | |
| Longmont Water Heaters | 5.0★ (191) | In Longmont |
| Lucas Boilers | 5.0★ (2) | In Longmont |
| McColl Electrical Services, LLC | 4.8★ (49) | In Longmont |
| Metaltech HVAC/DUCT Repair Service | 5.0★ (12) | In Longmont |
| Nesheim's | 4.8★ (311) | In Longmont |
| Pure Air Solutions | 4.8★ (305) | 17 mi |
| Shepherd Heating and Air | In Longmont | |
| Tico HVAC LLC | 5.0★ (294) | 17 mi |
| Touchstone Commercial Building Services | 3.0★ (2) | In Longmont |
| Trusted Longmont HVAC Services | In Longmont |
National price ranges in USD, not adjusted for Longmont. Each row names its basis and the month we checked it.
| Job | Low | Typical | High | Basis | Checked |
|---|---|---|---|---|---|
| AC replacement | $3,887 | $5,978 | $8,073 | Per system, installed (unit plus labor); typical range of customer-reported jobs. US national range | October 2026 |
| Furnace replacement | $2,823 | $4,814 | $6,896 | Per system, installed; typical range of customer-reported jobs. US national range | October 2026 |
In Colorado, furnace and heat pump calls peak in the coldest winter weeks and AC calls in summer heat waves. Spring and fall are the easiest times to book maintenance or a replacement.
We scored 480 Longmont HVAC contractors 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 October 22, 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 Longmont 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 |