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Find Septic system installers and replacers in Seattle

Avatar for A Advanced Septic
A Advanced Septic
4.3(
120
)

Serving Seattle, WA and surrounding areas

Approved

In business since 2006

Free estimates

Emergency services offered

"We had another company quote us $5000 to replace the septic pump, when we called A-Advanced they quoted us $2000 for the same job. Also came out to fix the electrical that wasn't working that the first company didn't inform us of. When the following weekend we had the issue again they came out and did more diagnostics and fixed the problem. All 5 of the people we have had come out have been very professional, knowledgeable, and friendly. 5 stars all the way."
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+8

Response time2 days
Response rate85%
11 neighbors recently requested a quote
Ron Hemley Septic Installations, Inc.
5.0(
2
)

Serving Seattle, WA and surrounding areas

Approved

In business since 1980

Free estimates

Offers commercial services

"If you do not make your first call to Hemley's, your making a big mistake. This company stand above the rest for their professionalism, work & business ethic's and their customer service at a fair price. This company should be the first one you call, they will assess and find the best solution which many other contractors wont do. If the scale went to 10, I would give them an 11."
Response time6 days
Recommended by100%of homeowners
Avatar for Whitworth Excavating, Inc.
Whitworth Excavating, Inc.
5.0(
3
)

Serving Seattle, WA and surrounding areas

Approved

In business since 1986

Free estimates

Emergency services offered

Whitworth Excavating, Inc. is the premier excavating company serving Kitsap County and surrounding areas for almost 4 decades. Our #1 goal as a company is having complete customer satisfaction and there is no job that is too big or too small. We offer both residential and commercial - If you want the job done right, call Whitworth today!

Kitsap Humane Society
Kitsap Humane Society
Net Systems
Net Systems
Carriage Homes

+19

Response time2 days
Recommended by66%of homeowners
Avatar for JT Industrial, LLC
JT Industrial, LLC
4.8(
4
)

Serving Seattle, WA and surrounding areas

Approved

In business since 2018

Free estimates

Offers commercial services

JT Industrial LLC is owned by Josh and Kristen Rodrigues. Josh has 17 years of experience in the excavation and trucking industry with a foundation working for his Grandfather at Zimmer Construction. He later moved on to managing an excavation team for Chinook Contractors before setting out on his own with JT Industrial LLC. Kristen has a background in business management and customer service. From managing a team for REI to working as a flight attendant for Alaska Airlines, her understanding of customer needs is expansive. Kristen, Josh and their team are dedicated to excellent workmanship, integrity in all business dealings and delivering competitive pricing for the quality of work. As an excavating contractor, we’re passionate about the work we do and love seeing new and interesting projects cross our desk. Our talented team and foundational knowledge make us your first choice for any of your excavation and trucking needs. Give us a call and let us know how we can help!

Development site
Grading
Manhole excavation
Manhole installation
Manhole excavation

+24

Response time1 day
1 neighbors recently requested a quote
Recommended by50%of homeowners
Avatar for Iron Earth Construction LLC
Iron Earth Construction LLC
5.0(
4
)

Serving Seattle, WA and surrounding areas

Approved

In business since 2021

Free estimates

Credit card accepted

"They quickly assessed the situation, gave a reasonable quote, and were very proficient and professional. My condo unit was under contract and a water leak caused by another unit needed to be repaired asap and they did it. Also kept me well informed."
Before
During rooftop build
Rooftop Deck during
AFter
Installation of Euro Fencing

+43

Response time3 days
12 neighbors recently requested a quote
Recommended by75%of homeowners
Freedom Excavation
New to Angi

Serving Seattle, WA and surrounding areas

Approved

In business since 2019

Free estimates

Credit card accepted

Freedom Excavation is committed to excellence every aspect of our business. We uphold a standard of integrity, bound by fairness, honesty, and professional responsibility. Our distinction is the quality of service we bring to our customers as well as our ability to give you a quick, fair, and accurate estimate. Accurate knowledge of our trade, combined with ability is what makes is true professionals. Above all, we are watchful of our customers' interests and make their concerns the basis of our business.

Response time10 hrs
10 neighbors recently requested a quote
Showing 1-10 of 43
FAQs for septic system installation and replacement projects in Seattle, WA

The smallest standard septic system uses a 500-gallon tank, which costs between $875 and $1,150 installed. This size works well for single-occupant dwellings with minimal wastewater production. However, many local regulations specify minimum tank sizes, so check with your building department before committing to this compact option. Some jurisdictions require at least 750 gallons regardless of home size to ensure adequate waste processing capacity.

The installation timeline varies based on site conditions, permit processing, and contractor schedules. The process includes obtaining permits, conducting soil tests, excavation, tank placement, leach field construction, and final connections. Weather conditions, soil challenges, and inspection scheduling can all affect the overall timeline. It's wise to begin planning well in advance of when you need the system operational.

The most economical approach is to install a conventional anaerobic system with a plastic tank. To minimize costs while maintaining legality, obtain multiple quotes from licensed installers, consider scheduling during their slower seasons, and handle basic site preparation yourself. Never skip permits or required testing to save money—illegal installations can result in significant fines and mandatory removal, ultimately costing far more than doing it right initially.

Regular pumping helps prevent system failures and extends operational life. Most small systems require pumping every three to five years, though frequency depends on household size and usage patterns. Pumping services cost between $290 and $530, making this maintenance expense relatively minor compared to potential repair costs ranging from $500 to $2,600 for neglected systems. Establishing a regular maintenance schedule based on your installer's recommendations helps avoid costly emergency services.

The Seattle, WA homeowners’ guide to septic system installations and replacements

From average costs to expert advice, get all the answers you need to get your job done.