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
I'm a Master Plumber. I provide Quality and Perfection. That is my number one goal. I do the job correctly and professionally. I'm not the cheapest, but I am skilled at what I do.
Notes : We charge a $100 service fee, but if GNK Plumbing is hired for the job the fee will be waived.
Monday to Saturday from 8.00 Am to 6.00 Pm
Overview
Current Top Pro
Hired 343 times
5 similar jobs done near you
Background checked
License verified
2 employees
21 years in business
Business hours
This pro hasn't listed their business hours.
Payment methods
This pro accepts payments via Cash, Check, and Credit card.
Top Pro status
Top Pros are among the highest-rated, most popular professionals on Thumbtack.
2025
2024
2023
Credentials
License verified
Plumber – Master
License state: MA
Background checked
Passed by Jean Kossaifi on Jan 4, 2023.
Services offered
Pipe issues
Repair urgency
I work on non-urgent repairs
I work on urgent repairs
Flooding status
Yes
Projects and media
Projects and media
Reviews
Customers rated this pro highly for professionalism, work quality, and responsiveness.
Excellent 4.9
230 reviews
5
97%
4
1%
3
0%
2
1%
1
1%
Your trust means everything to us. Learn about our review guidelines.
Read reviews that mention:
Kathy B.
2 weeks ago
•
Hired on Thumbtack
Jean was extremely responsive. I appreciated how quickly he assessed and fixed the plumbing issue. I would definitely hire again.
Details: Only one drain has issues • Other issue • House
Plumbing Drain Repair
Samantha R.
Aug 25, 2026
•
Hired on Thumbtack
Responded to my inquiry right away and came the next day and was able to resolve our hot water heater and plumbing issues quickly and reasonably. Good communication and very professional and respectful. Thanks!
Water Heater Repair or Maintenance
Laura F.
Jun 2, 2026
•
Hired on Thumbtack
Jean got right back to me so I scheduled with him for the next day. He came and found no leaks, which is good but he also checked out all the plumbing and changed a part in the toilet so the water would stop running all day and night. He's a nice man and he doesn't try to sell you anything that you don't need. He's our new plumber going forward!
Details: No, repair is not urgent • No, the building is not currently flooded • House
Plumbing Pipe Repair
Bill B.
May 14, 2026
•
Hired on Thumbtack
Jean at GNK Plumbing was hired to replace a kitchen faucet. Jean is responsive and showed up within a day after being initially contacted. Upon arrival, he got right to work and worked through a few minor problems he encountered replacing faucet. Jean also noticed and replaced a leaky outside spigot turn-off valve located in my basement. Jean does quality work for a very reasonable price. For example, another larger plumbing company quoted me a price 3x more for the same job. You will not be disappointed by hiring Jean for any of your plumbing projects.
Details: 1 sink • One handle controls both hot and cold water • 1 faucet • A month ago or longer
Sink or Faucet Repair
Olga F.
May 30, 2026
•
Hired on Thumbtack
Great job! We appreciated the punctuality and very professional communication, but above all - the advice we received on how to maintain plumbing in our home.
Details: Yes, repair is urgent • Only one drain has issues • Unpleasant odor • House
Plumbing Drain Repair
FAQs
What should the customer know about your pricing (e.g., discounts, fees)?
I offer multiple options with different proces and offer discounts depending on the job
What is your typical process for working with a new customer?
meet to customer assess the issue and discuss the options for the solution and make sure the customer is comfortable with our work
What education and/or training do you have that relates to your work?
I completed my journey license and master license. I have attended trainings around boilers and I complete yearly trainings to stay up to date with the latest procedures
