GNK plumbing services

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Licensed

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Why this pro?

This pro has been in business for 20 years and provides plumbing pipe installation and repair services, along with sink and faucet work. Customers say they're clean, professional, and responsive.

Summarized from the pro's profile. Review their profile for the latest.

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 342 times

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

Faucet / handle type

One handle controls both hot and cold water

Separate handles control hot and cold water

Projects and media

Reviews

Customers rated this pro highly for professionalism, work quality, and responsiveness.

Excellent 4.9

229 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

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

Marie S.

Mar 21, 2026

•

Hired on Thumbtack

Jean was very professional and did a great job at fixing my kitchen faucet. He knew exactly what was wrong and completed the job in a timely manner. He made sure to clean and remove any residue. He did not leave any mess behind.
I will definitely rehire him.

Details: 1 sink • One handle controls both hot and cold water • 1 faucet • A month ago or longer

Sink or Faucet Repair

Maria V.

Apr 13, 2026

•

Hired on Thumbtack

Details: No, repair is not urgent • No, the building is not currently flooded • Other pipe issue • Sink • House

Plumbing Pipe 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