How Much Does It Cost to Replace a Septic Tank in Denver, CO? [2026 Data]

The cost to replace a septic tank in Denver, CO, ranges from $5,290 to $12,696. Most homeowners in the city pay around $6,348. Colorado has strict regulations on septic systems, and working with a pro is the best way to ensure compliance. Local pros are also accustomed to working with Denver, CO's heavy clay soil and ensuring proper drainage. Consider cost factors as you prepare to budget for this project.

Septic Tank Cost Factors 

Tank size will most influence the cost to replace a septic tank in Denver, CO. The size you need depends on your home's size and is calculated by the number of bedrooms. Tank material will also factor into the total price. For example, concrete and plastic septic tanks are less expensive than fiberglass ones. 

Size

The septic tank size you need depends on the number of bedrooms your home has. For a three- or four-bedroom home, you’d need a 1,000-gallon septic tank, which costs $950 to $1,585 for the tank alone.

Larger houses have more sinks, toilets, bathtubs, and other wastewater sources that flow into the septic tank. As tank size increases, so do costs.

Septic Tank Material

Septic tanks are commonly made of plastic, concrete, or fiberglass, with fiberglass often being the most expensive. Here’s how much a tank costs based on its material.

Demolition, Prep, and Cleanup

Replacing a septic system often involves excavation and clearing trees or roots. Since excavation can be a messy work, many homeowners add sod over their yards or even regrade their yards at the end of a septic tank replacement for a finished look.

Septic Tank Pro Costs

On average, septic tank pros in Denver, CO, charge an hourly rate between $70 and $80. Permit and inspection fees vary based on the type of work completed and any other required tasks, such as those related to floodplains. Permits cost between $300 and $500, while inspections cost between $150 and $250. 

Your local septic pro can handle obtaining such permits and inspections based on the scope of the work. Aside from helping with local regulations, a pro will best recommend the type of septic tank for your home, based on size.

Does Replacing a Septic Tank Increase Home Value?

Yes, replacing your septic tank increases home value, with the average homeowner seeing a 5% to 10% increase. New septic tanks portray a move-in-ready home to potential buyers, enhancing buyer confidence. With strict regulations in Colorado for septic systems, the best way to ensure your septic tank positively impacts your home's value is to work with a licensed septic pro.

How Angi Gets Its Local Cost Data 

To help homeowners plan their next project, Angi provides readers with carefully researched cost data and upholds strict editorial standards. We start with national average project costs, which we collect by analyzing competitor information, retailer material costs, and input from professional contractors. We then apply local price index data to calculate location-specific estimates that reflect what homeowners typically pay in their local area. To do that, we use data from the U.S. Bureau of Economic Analysis (BEA), including its Regional Price Parities (RPPs), which measure price differences across cities. This helps us account for differences in labor, materials, and overall cost of living, so estimates in higher- or lower-cost areas better reflect real-world local pricing.

Every estimate undergoes a thorough editorial review to verify accuracy, consistency, and alignment with observed market conditions.

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