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Find Septic system installers and replacers in Seattle

Avatar for A Advanced Septic
A Advanced Septic
4.4(
108
)

Serving Seattle, WA and surrounding areas

Approved

In business since 2006

Free estimates

Emergency services offered

"Initially I had a tank alert go off and called A-Advance Septics to pump my septic system and troubleshoot the alarm. The required services occurred over 2 days (12/1 & 12/3/2020). On 12/1, Matt V. was the service tech that came to locate/dig the tank lids. Matt was very professional in his work when pumping out the two tanks (septic and pump). Matt was very informative and helpful answering my questions, especially when I did not know about the pump tank plus the need to clean outlet baffle filter annually. Thus the need for replacement lid/risers for future access. Ray B. and Doug G. were also very professional and were able to troubleshoot the tank alarm issue and isolate to failed pump (26 years old) and need to be replaced along with new junction box. On 12/3, EJ M. and Doug G. returned to install 3 sets of lid/risers, junction box, and pump replacement. EJ and Doug were very professional in their work and were also informative upon answering my questions. Overall I was very satisfied on the work that was completed and definitely would recommend and call A-Advanced Septics for future service (I liked the feature on the new lids with your company name and phone number embossed, no need to jog my memory or scramble looking for company name or phone number). Thanks, Chester F."
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+8

Response time2 days
Response rate85%
10 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
2 neighbors recently requested a quote
Recommended by66%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
4 neighbors recently requested a quote
Recommended by75%of homeowners
Avatar for MRJ Excavating and Engineering LLC
MRJ Excavating and Engineering LLC
5.0(
1
)

Serving Seattle, WA and surrounding areas

Approved

In business since 2022

Free estimates

Emergency services offered

Clearing and removal of brush, excavation, grading, underground utilities, storm drainage, ditches, driveway gravel, site preparation for residential home, garage or shop. Emergency work, storm clean up, demolition

Foundation Excavation
Drainage and grading project
Foundation Excavation
Drainage and grading project
Foundation Excavation

+32

6 neighbors recently requested a quote
Recommended by100%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
8 neighbors recently requested a quote
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.