Ritchie's Insulation & General Contracting
“I called on a Friday the inspection and quote occured the following Monday and my attic was brought up to an R60 value the following Friday.”
Best General Contractors in St. Thomas, ON
15 companies listed · 9 in St. Thomas · 2 open 24/7 · 5 open weekends · 10 rated 4.5+
Data verified October 21, 2026
Doug Tarry Homes
“Their proven track record and reputation for exceptional craftsmanship set them apart from other builders, and that level of quality is evident throughout every stage of the homebuilding process.”
Cedar Ridge Construction
“Paul has done a number of jobs for us and would highly recommend him.”
Jay Okkerse Contracting
“The guys went above and beyond and even put my furniture back into place after I was unable to.”
MP Custom Homes
“Even the tradesmen who came to hook up our appliances were impressed as they walked through the house, commenting on the quality of the materials used”
Elgin Construction Company Limited
“Although it's been a long 3 months having to live through this, Jeremy and his crew were working hard every day to get the project completed on time.”
Listed for homeowners in and around St. Thomas, ON, these 15 companies take on multi-trade work, from a basement build-out to a full renovation. What each one says about licensing, hours and the work it takes on comes from its own website; ratings and quotes come from public reviews.
Area overview: St. Thomas, ON
Of the 15 companies we list here, 9 are in St. Thomas itself and 6 come from London (4, 24 km), Port Stanley (1, 11 km) and Aylmer (1, 17 km). The companies on this page are rated from 3.1 to 5.0 across 847 reviews; 7 have 50 or more reviews and 10 are rated 4.5 or higher. The topics that come up most in reviews of the companies on this page are "price" and "quality". 2 are open around the clock; 5 are open on Saturdays and 2 on Sundays. Domain records put 7 websites of the companies on this page at ten or more years old; the oldest dates from 1999. 4 offer emergency call-outs; 1 offers financing or payment plans; 5 give free estimates; 3 are family- or locally-owned and 1 lists coupons or special offers. We have a website on file for 14 of the companies on this page; 11 publish a contact page; 11 list a public email and 1 takes bookings online. We count these figures across the companies on this page; distances are straight-line, and hours and prices change, so confirm the details with the company before you book.
Why do some of these firms sit outside St. Thomas?
Only 9 of the 15 companies here are based in St. Thomas. The rest come from other towns within 25 km. Crews travel to the work, so the office address matters less than whether they will send the same people every morning and what travel time does to the price.
Circelli Steel Ltd
“I highly recommend this company, they are very kind people and fulfill all the jobs you need, perfect welding and construction of your fantastic projects, they respect their word and respect the dates I recommend”
Elgin Contracting & Restoration
“Organization, lovely people to work with.”
Scott's Home Works
“We had plumbers here at the same time and they swept the floor behind them.”
First General London/Middlesex
“They handled the entire renovation process efficiently, paying close attention to detail while completing the work in a timely manner.”
1st Choice Home Solutions
“When we contacted 1st Choice they got back to us right away and we had our onsite consult immediately.”
Power House Construction
“Carpets were placed across our floors, into the hall and right to the elevator of our condo/apartment; they were swept each night before leaving the premises.”
DLS Electric (London) Inc.
“They are good communicators, have great people (this time it was Mike R and Nikki), do good work, are tidy and pleasant to deal with.”
Teichroeb Exteriors Inc.
“Came and saw what we needed and did an excellent install job.”
Backyard Escape Studios
“Backyard escapes team also provided a lot of help and advice along the way, we never felt pushed into making a decision and they were very flexible.”
Why these companies made our list
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