822 HVAC contractors ranked by CR ScoreUpdated 0 paid placements in this rankingHow we rank →
Best overall in Markham: Reliance Heating, Air Conditioning & Plumbing, CR Score 94/100; 4.9★ from 10,870 Google reviews; open 24/7.
Best for emergencies (open 24/7): ICare Home Comfort, posts 24/7 hours; ranked #2 of 822.
Most-reviewed: Enercare, 11,186 Google reviews at 4.8★, the most of 822 ranked; ranked #11.
Rankings can't be bought. Contractors can't pay to change their rank or score. How we rank
822 Markham HVAC contractors are ranked here by CR Score, from 8 published factors. 324 are open 24/7, 604 open Saturdays and 492 open Sundays, based on posted hours. The median Google rating is 4.9★ across 822 rated businesses.
| Rank | Business | CR Score | Google rating | Based in | Hours | Best for |
|---|---|---|---|---|---|---|
| 1 | Reliance Heating, Air Conditioning & Plumbing | 94 | 4.9★ (10,870) | Richmond Hill, 10 km away | 24/7 | Overall |
| 2 | ICare Home Comfort | 92 | 4.9★ (836) | Markham | 24/7 | Emergencies |
| 3 | Go Lime | 92 | 4.8★ (6,512) | North York, 12 km away | 24/7 | — |
| 4 | High Efficiency Cooling & Heating Inc. | 92 | 4.8★ (1,319) | Markham | 24/7 | — |
| 5 | Reliance Heating, Air Conditioning & Plumbing | 91 | 4.7★ (9,158) | North York, 11 km away | 24/7 | — |
| 6 | Mersey Heating and Air Conditioning | 91 | 4.8★ (3,715) | Scarborough, 10 km away | 24/7 | — |
| 7 | Royal Air Solutions | 91 | 5.0★ (271) | Markham | 24/7 | — |
| 8 | Superior Care Home Services Inc. | 91 | 5.0★ (266) | Markham | 24/7 | — |
| 9 | Enercare | 91 | 4.9★ (9,609) | Vaughan, 25 km away | 24/7 | — |
| 10 | Service Express HVAC | 91 | 4.9★ (384) | Markham | 24/7 | — |
Ordered by CR Score, a 0–100 score from 8 published factors. Paid placement never changes the order.
Scores below: based on 6 of 8 factors; credentials and recency not yet collected. Hatched segments mark factors we don't have yet.
Ranked #1 in Markham
Based in Richmond Hill, 10 km away
Ranked #1 because of its Google rating and availability: 4.9★ from 10,870 Google reviews, open 24/7.
Based in Markham
Ranked #2 because of its Google rating and availability: 4.9★ from 836 Google reviews, open 24/7.
Based in North York, 12 km away
Ranked #3 because of its Google rating and availability: 4.8★ from 6,512 Google reviews, open 24/7.
Based in Markham
Ranked #4 because of its Google rating and availability: 4.8★ from 1,319 Google reviews, open 24/7.
Based in North York, 11 km away
Ranked #5 because of its Google rating and availability: 4.7★ from 9,158 Google reviews, open 24/7.
Based in Scarborough, 10 km away
Ranked #6 because of its Google rating and availability: 4.8★ from 3,715 Google reviews, open 24/7.
Based in Markham
Ranked #7 because of its Google rating and availability: 5.0★ from 271 Google reviews, open 24/7.
Based in Markham
Ranked #8 because of its Google rating and availability: 5.0★ from 266 Google reviews, open 24/7.
Based in Vaughan, 25 km away
Ranked #9 because of its Google rating and availability: 4.9★ from 9,609 Google reviews, open 24/7.
Based in Markham
Ranked #10 because of its Google rating and availability: 4.9★ from 384 Google reviews, open 24/7.
Based in North York, 23 km away
Ranked #11 because of its Google rating and availability: 4.8★ from 11,186 Google reviews, open 24/7.
Based in Markham
Ranked #12 because of its Google rating and availability: 4.9★ from 366 Google reviews, open 24/7.
Based in Markham
Ranked #13 because of its Google rating and availability: 4.8★ from 583 Google reviews, open 24/7.
Based in Markham
Ranked #14 because of its Google rating and availability: 4.8★ from 480 Google reviews, open 24/7.
Based in Ajax, 13 km away
Ranked #15 because of its Google rating and availability: 4.8★ from 2,085 Google reviews, open 24/7.
Based in Vaughan, 20 km away
Ranked #16 because of its Google rating and availability: 5.0★ from 1,314 Google reviews, open 24/7.
Based in Pickering, 18 km away
Ranked #17 because of its Google rating and availability: 4.9★ from 1,570 Google reviews, open 24/7.
Based in North York, 9 km away
Ranked #18 because of its Google rating and availability: 4.9★ from 529 Google reviews, open 24/7.
Based in Oshawa, 32 km away
Ranked #19 because of its Google rating and availability: 4.9★ from 8,942 Google reviews, open 24/7.
Based in Pickering, 18 km away
Ranked #20 because of its Google rating and availability: 4.9★ from 1,230 Google reviews, open 24/7.
Based in Markham
Ranked #21 because of its Google rating and availability: 4.7★ from 490 Google reviews, open 24/7.
Based in Markham
Ranked #22 because of its Google rating and availability: 4.8★ from 256 Google reviews, open 24/7.
Based in Richmond Hill, 10 km away
Ranked #23 because of its Google rating and availability: 4.9★ from 435 Google reviews, open 24/7.
Based in Richmond Hill, 11 km away
Ranked #24 because of its Google rating and availability: 4.9★ from 465 Google reviews, open 24/7.
Based in Markham
Ranked #25 because of its Google rating and availability: 4.8★ from 207 Google reviews, open 24/7.
#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 822 ranked HVAC contractors here; the rest are on their profiles.
20 more HVAC contractors within 40 km that we can't rank yet: too few reviews, or a trade we couldn't confirm. Listed A to Z.
| Business | Google rating | Distance |
|---|---|---|
| Aas | 4.0★ (2) | 15 km |
| ABM - Facility Services | In Markham | |
| Active Air Comfort Inc | 3.0★ (2) | 16 km |
| Airsource Mechanical | In Markham | |
| Airzone Heating & Cooling, HVAC contractor | 5.0★ (2) | 11 km |
| BR-HVAC | 5.0★ (2) | 11 km |
| CARLSON MECHANICAL SERVICES LTD | In Markham | |
| Caspian Breeze Heating and Air Conditioning | 5.0★ (2) | 13 km |
| Cool Air HVAC Services | 5.0★ (1) | In Markham |
| EnerBee | In Markham | |
| Exalted Services | 4.9★ (100) | In Markham |
| Home Services at The Home Depot | 3.5★ (2) | 11 km |
| Maple Star Heating, Cooling and Plumbing | 5.0★ (1) | In Markham |
| Markham Heating and Air Conditioning by Freezing Hot Mechanical | 5.0★ (2) | In Markham |
| N And D Plumbing & Heating | 3.0★ (2) | In Markham |
| Reliance Heating, Air Conditioning & Plumbing | 4.7★ (1,854) | 26 km |
| Svmk Hvac Services | 5.0★ (2) | 4 km |
| Unitech Home Comfort | 5.0★ (2) | 15 km |
| Whole Home Savings | 2.5★ (2) | 6 km |
| Worthing Heating And Cooling Inc | 5.0★ (2) | In Markham |
US national ranges converted to CAD, not adjusted for Markham. Each row names its basis and the month we checked it.
| Job | Low | Typical | High | Basis | Checked |
|---|---|---|---|---|---|
| AC replacement | CA$5,460 | CA$8,400 | CA$11,350 | Per system, installed (unit plus labor); typical range of customer-reported jobs. US national range converted at 1.4054 CAD per USD (Bank of Canada, October 20, 2026) | October 2026 |
| Furnace replacement | CA$3,970 | CA$6,770 | CA$9,690 | Per system, installed; typical range of customer-reported jobs. US national range converted at 1.4054 CAD per USD (Bank of Canada, October 20, 2026) | October 2026 |
In Ontario, 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 822 Markham HVAC contractors on 8 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. Unknown factors are left out of the score, 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 Markham data |
|---|---|---|---|
| Reputation | 35% | Bayesian-adjusted Google star rating | Measured |
| Credentials | 15% | Active state license 0.6, bond 0.2, workers’ comp 0.2 | Not yet collected |
| Review volume | 10% | log10(reviews + 1) against the list maximum | Measured |
| Recency | 10% | Share of reviews from the last 12 months | Not yet collected |
| Availability | 10% | Weekly open hours, Saturday, Sunday, 24/7 or same-day | Measured |
| Trade focus | 10% | Google main category 1.0, business name 0.7, additional category 0.5 | Measured |
| Proximity | 5% | 1.0 when based in the city, falling to 0 at the trade’s radius | Measured |
| Completeness | 5% | Website, photos, description, hours, claimed profile (0.2 each) | Measured |