If you hire this pro, you’re covered by a money-back guarantee. Learn more
If you hire this pro, you’re covered by a money-back guarantee. Learn more
About
Mammoth Plumbing, Heating & Air Conditioning delivers massive service with dependable results. We specialize in residential plumbing, heating, and HVAC solutions, handling everything from leak detection and gas line repairs to water heaters, furnaces, and AC systems.
Our licensed and experienced technicians show up on time, communicate clearly, and treat your home with respect. We focus on honest recommendations, quality workmanship, and long-lasting solutions — no upselling, no shortcuts.
Whether you need an urgent repair, routine maintenance, or a full system installation, Mammoth is built to handle jobs of all sizes with professionalism you can trust.
Reliable. Experienced. Mammoth results.
Overview
Hired 1 time
Serves Commerce City, CO
Background checked
License verified
2 employees
2 years in business
Business hours
Sun6:00 am - 8:00 pmMon6:00 am - 8:00 pm
Payment methods
This pro accepts payments via Cash, Check, Credit card, PayPal, Venmo, and Zelle.
Credentials
License verified
Plumber – Master
License state: CO
Background checked
Passed by Jeffrey Dunlap on Jan 7, 2026.
Services offered
Size of installation
A few pipes
One or more entire rooms
An entire home
Other pipe installation
Installation needed
Hook-up appliance or fixture
Install pipe to one or more rooms
Install pipe to home (from street)
Install gas line
Property type
House
Condo/Apartment
Townhouse
Business
Projects and media
Projects and media
Reviews
Customers rated this pro highly for professionalism, value, and work quality.
Exceptional 5.0
35 reviews
5
100%
4
0%
3
0%
2
0%
1
0%
Your trust means everything to us. Learn about our review guidelines.
Read reviews that mention:
Stephen S.
Mar 9, 2026
•
Hired on Thumbtack
Jeff from Mammoth plumbing made several plumbing upgrades repairs for our home renovation project. His work was impeccable and is very knowledgeable. Jeff communicated our options very clearly and helped us to understand all of our options and decide on the best value for us. 10/10 would recommend. Easiest contractor to work with throughout the entire home renovation project.
Details: Other pipe installation needs • Other pipe installation • House
Plumbing Pipe Installation or Replacement
Dianna S.
2 weeks ago
•
From Google
Great communication, great job, great guy. Knows what hes doing, replaced my water heater and was in and out fast. Support your local small businesses and veterans. Im definitely going to use him again.
Mammoth Plumbing Heating and Air Conditioning's reply
Thank you so much for your wonderful review, Dianna! We truly appreciate your support and are thrilled you were happy with your water heater replacement. At Mammoth Plumbing Heating and Air Conditioning, we’re grateful for customers like you and look forward to helping you again!
Claire L.
Aug 12, 2026
•
From Google
Fantastic service!Jefferey showed up right on time, quickly diagnosed our leak, and got into the repair even though it was a last minute request late afternoon. He is professional and reasonable pricing too. Highly recommend to anyone needing a reliable plumber in the area
Mammoth Plumbing Heating and Air Conditioning's reply
Thank you so much, Claire, for your wonderful review! We’re thrilled to hear Jefferey provided prompt and professional service, especially on short notice. Your recommendation means a lot to everyone at Mammoth Plumbing Heating and Air Conditioning! We appreciate your trust and support.
Brian G.
Aug 2, 2026
•
From Google
Have to give Jeff 5 stars only because there isnt more. Knowledgeable pro, if I need anything AC/heating I know who Im calling.
Mammoth Plumbing Heating and Air Conditioning's reply
Thank you so much, Brian, for your fantastic review! We're thrilled to hear Jeff provided such great service. Your trust in Mammoth Plumbing Heating and Air Conditioning for your AC and heating needs means a lot to us. We appreciate your support!
Michelle
Jul 16, 2026
•
From Google
I am very satisfied with Mammoth Plumbing. Jeff came to install a new water heater. I was informed when he was on his way so I was ready. He was professional and ready to work. I asked if he could fix the valve on the toilet after he arrived and he did. He saved me a lot of money compared to the other guys. I am going to be using him again to install a new HVAC system when I am ready. I would highly recommend Mammoth Plumbing, Heating and Cooling.
Mammoth Plumbing Heating and Air Conditioning's reply
Thank you so much, Michelle, for your wonderful review! We’re delighted to hear you had a great experience with Jeff and appreciate your recommendation. We look forward to helping you again with your HVAC system! – Mammoth Plumbing Heating and Air Conditioning
