
Jeff Costello is the Founder and Managing Broker of Tribeca NW Real Estate based in Bellevue, Washington. As a premier real estate broker serving Bellevue and the Greater Seattle Area, Jeff leads one of the region's most respected real estate teams. Backed by a proven track record of successful transactions, Jeff's team has closed 1,766 total sales, including 246 successful transactions in the last 12 months alone, spanning a price range of $16,000 to $4,000,000.
Jeff’s career in the real estate industry began in 2004 when he went to work in wholesale mortgage banking, gaining deep expertise in mortgage loans. In this role, he collaborated closely with lenders, brokers, and underwriters to structure and qualify complex files. He successfully transitioned to become a licensed real estate agent and REALTOR® in 2007. This foundational financial background gives him a distinctive edge in guiding buyers and sellers through complicated real estate transactions with confidence and care.
Whether you are looking to buy or sell a home on the Eastside, Jeff offers hyper-local expertise across specific Bellevue submarkets, including West Bellevue, Downtown Bellevue, Eastgate, and Bridle Trails. As a listing agent, he leverages market data and targeted digital exposure to help homeowners sell for maximum value. For home buyers searching in competitive neighborhoods, he empowers clients with local insights and the negotiation skills needed to handle multiple-offer situations and execute aggressive escalation clauses.
In 2017, Jeff founded Tribeca NW Real Estate to elevate the standards of real estate service in the Pacific Northwest. What began as a small team of three professionals has since grown into a thriving brokerage with more than 35 team members—all united by a shared commitment to excellence, collaboration, and results. Jeff continues to lead the firm’s growth, mentoring agents and refining the systems that drive long-term client satisfaction and success.
A lifelong resident of the Puget Sound area, Jeff combines deep local market knowledge with a genuine passion for his community. He holds professional designations with several top industry organizations, including active memberships in the National Association of REALTORS, the Seattle King County Association of Realtors, the Council of Real Estate Specialists, and the Real Estate Buyers Agent Council. Outside the office, he enjoys spending time with his wife, three children, and Yorkshire terriers—whether boating on the Sound, exploring the Hawaiian Islands, or cheering on his son’s lacrosse team.
Unusual Fact:
I instructed over 600 hours of continuing education in a single year.
Perfect day:
Out in nature hiking or kayaking with my partner and pup.
Born In:
Redmond, WA
First job:
Managing a print & ship center.
The best advice you've ever received:
Kind and clear beats nice and vague.
The best part of this team is:
The people and our culture of collaboration.
Proudest Moment:
Completing my MBA degree while working full time.
Favorite Food:
Birria Vampiros
The superpower I'd want is:
Teleport anywhere in the world.
Favorite Western Washington Location:
Hoh Rain Forest






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