*The Angi rating for Basement Waterproofing companies in Ontario, CA is a rating based on verified reviews from our community of homeowners who have used these pros to meet their Basement Waterproofing needs.
*The HomeAdvisor rating for Basement Waterproofing companies in Ontario, CA is a rating based on verified reviews from our community of homeowners who have used these pros to meet their Basement Waterproofing needs.
Last update on May 23, 2026
Serving Ontario, CA and surrounding areas
Approved
In business since 1992
Free estimates
Small jobs welcome
"Bill and his crew were extremely professional and helped assess the issue and fix my waterproofing problems quickly. Highly recommend."
Serving Ontario, CA and surrounding areas
Approved
In business since 1992
Free estimates
Offers commercial services
At 21st Century Painting and Waterproofing, we offer the best service for your waterproofing needs. We have been in business for over 20 years and have the skill and expertise you need. We look forward to working with you. Give us a call today!
Serving Ontario, CA and surrounding areas
Approved (Corporate)
In business since 1992
Free estimates
Emergency services offered
"Dan was here this morning, showed him where water was leaking in over our slab and ruining the flooring in the master bedroom. He gave me the full range of possible remedies, from installing a eaves gutter on the roofline outside the bedroom to a full (very expensive) sealing of the entire exterior foundation. And actually recommended that we start with the gutter (which I can do myself) and then monitor the area next rainy season and see if that fixes the problem. No pressure to hire them or spend big $$, just good advice. Couldn't have asked for more. Highly recommended- this is real service!"
+323
Serving Ontario, CA and surrounding areas
Approved
In business since 1981
Free estimates
Emergency services offered
"I returned home from a trip and found water all over my downstairs bathroom and adjoining shed. It was late afternoon and I called Western Rooter who agreed to come out first thing the next day, I had a pretty sleepless night. Rene showed up the next day and assessed the situation and started clean up. Tony soon joined him and the two worked all day until after dark and helped me with cleanup and putting things right. They explained to me what they were doing and why along the way. I felt they charged a fair price. I am so grateful for their service and highly recommend Western Rooter."
+542
Serving Ontario, CA and surrounding areas
Approved
Super Service Award Winner
In business since 2024
Free estimates
Emergency services offered
"Excellent, could not be happier with service."
+18
Serving Ontario, CA and surrounding areas
Approved (Corporate)
In business since 1995
Free estimates
Warranties offered
"Their initial price was really high and I declined. But, when they were left with a crew stuck in my area due to a cancelled job, they were really willing to negotiate. The guys were good and did a good job. I'm really happy I had my slab lifted."
+16
Serving Ontario, CA and surrounding areas
Approved
In business since 2017
Free estimates
Emergency services offered
"Nick was amazing and got a big problem done for a reasonable price. He will be my forever plumber now"
+100
Serving Ontario, CA and surrounding areas
Approved
In business since 2019
Free estimates
Credit card accepted
RSF Construction Inc. is a leader in providing our customers with the highest quality service in an honest, efficient, and professional way. Our pledge is to create successful relationships with our customers, employees and community by building trust, treating every project with the utmost integrity and exceeding expectations. We look forward to working with you!
Serving Ontario, CA and surrounding areas
In business since 2016
Free estimates
Credit card accepted
It can be a daunting task looking for not only the right contractor for your job but also the right contractor for you. We completely understand what you're going through. We know every customer has different desires, different needs and different schedules. We're not only here to turn your ideas into reality but to make it a memorable experience every step of the way. Call us right now, no matter where you are in the planning process.
Serving Ontario, CA and surrounding areas
In business since 2016
Free estimates
Credit card accepted
"We worked with Ali (sales manager) and Tony (project manager), who took the time to design a project that made sense for our property and our budget, made a number of suggestions and recommendations and were never pushy or tried to "sell" us on something. The crew really went above and beyond to provide top quality workmanship and overall we were in very good hands. Highly recommended!"
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