Septic tank replacement cost
Septic tank replacement cost
Replacing just the tank typically runs $1,500–$6,000 installed. The estimator below is preset to tank-only — pick your size, material, and state.
Estimate only — get 2–3 quotes from licensed installers. Coefficients are national calibration defaults (June 2026); your costs will vary.
The short answer
What a new tank costs
A tank-only replacement typically costs $1,500–$6,000 installed. That covers pumping out and removing the old tank, the new tank itself, excavation, and reconnection. The price climbs with tank size (more bedrooms), tank material, and how hard the tank is to reach — a tank under a deck or driveway costs more to dig out than one in an open yard.
When the tank is the problem
Tank-only replacement makes sense when the tank has cracked, corroded, or collapsed but the drain field is still sound. If both are failing, a full replacement is usually the call. Either way, current code may require a larger tank than your original — confirm the minimum size with the tank size calculator before you buy.
Frequently asked questions
How much does it cost to replace just the septic tank?
A tank-only replacement usually runs $1,500–$6,000 installed, including pumping and removing the old tank, the new tank, and excavation. Larger tanks, fiberglass over concrete, and difficult access raise the figure.
When can I replace only the tank?
When the tank is cracked, collapsed, or corroded but the drain field still works. If the field has also failed, you are usually looking at a full system replacement.
Concrete, plastic, or fiberglass — which tank?
Concrete is the default and most durable; plastic is lighter and cheaper but can shift; fiberglass resists corrosion and is light but costs a bit more. The calculator lets you compare materials.
Does a new tank need a permit?
Yes. Even a like-for-like tank swap is permitted, and current code may require a larger minimum size than your old tank. Budget for the permit and possibly a larger tank.
How long does a septic tank last?
A concrete tank commonly lasts 40 years or more; plastic and fiberglass are also long-lived. The tank usually outlasts the drain field, which is why tank-only replacement is less common than field replacement.