Inspecting a septic system requires specialized knowledge that some plumbers may not have. Consider hiring a licensed septic system professional or company who can review your tank’s history and check it for leaks and blockages. They should also be able to recommend repair and maintenance tasks, such as pumping the tank and taking care of the drainfield. 

Here are the qualifications you should look for in a septic inspector:

• Licensing and insurance: Check your state’s licensing requirements for septic inspectors. In many states, you can check the online licensing board’s database to see if the pro’s license and insurance are active. 

• Experience: Look for plumbers or septic service companies that specialize in inspections. Read their customer reviews or ask for customer referrals to help validate their experience in septic inspections. 

• Professional memberships: Find out if the inspector is a member of an organization like the National Onsite Wastewater Recycling Association (NOWRA) or the National Association of Wastewater Technicians (NAWT).

• Fair pricing: Get price quotes from several local inspection services and pros to ensure you’re paying a fair price. 

For more tips, visit Thumbtack’s Smart Hiring page. 

Most septic system inspections allow plumbers to assess these performance measures:

• Leaks or cracks in the tank

• Clogs in pipe connections

• Ensuring tank size matches household demand

During an inspection, a professional may look for plumbing fixture odors or backups, which could indicate there’s a septic problem. They’ll likely check the sludge level and look for issues like waste leaking into the ground surface. 

Inspectors may also spot wet areas in the yard, standing water, excessive grass growth or odors that indicate there might be drainfield issues. They might also pump the tank to remove accumulated sludge and scum.

At the end of the inspection, be sure their final report includes any recommended repairs and maintenance tasks to keep your system running smoothly.

The national average cost of a septic inspection is around $455,* according to Thumbtack data. That said, prices tend to range from approximately $375 to $575.* 

There are many factors that can affect prices, including:

• Accessibility to the tank site. The harder it is for the inspector to get to the tank, the more expensive the project might be.

• Tank size and complexity. Tank sizes range from about 150 gallons to 1,500 gallons. The bigger and more complex the tank is, the more it might cost to get it inspected.

• Services and tools needed. Sometimes, a camera inspection may increase the cost. Also, if your inspector needs to pump and clean your tank, you can expect to pay more. 

*Data on file at Thumbtack. For a personalized cost estimate, request a quote from a professional.

In many cases, inspections are an essential part of owning a septic system. Inspections can help you avoid costly repairs by catching potential issues early. For example, an inspection can help prevent yard contamination or a system backup, which can get messy and expensive to fix. 

Also, consider the fact that the national average cost of septic tank inspections is around $455,* according to Thumbtack data, and they usually take just a few hours to complete. During the inspection, a professional might catch an issue that could cause your system to fail down the line — potentially saving you thousands of dollars to completely replace it.

*Data on file at Thumbtack. For a personalized cost estimate, request a quote from a professional.

As a general rule of thumb, septic tanks need to be inspected about every one to three years. If you haven’t had your system inspected within that timeframe, it might be time to schedule an appointment.

Keep an eye out for these other signs that indicate it might be time for an inspection:

• Slow-draining sinks, toilets or other plumbing fixtures 

• Foul odors in your home or near the septic tank

• Sewage backups or gurgling pipes

• Patches of unusually lush, green grass near your septic tank

• Visible damage to your septic system

Septic issues can take time to surface, but once they do, it's best to call a professional quickly. Faulty septic systems can pose serious health and safety hazards, so try to get yours inspected — and repaired — immediately.

A septic inspection gives you an opportunity to identify and fix problems in the tank, lines or drainfield before they become major problems. If your septic system fails an inspection, it could impact the safety of your waste disposal or even affect a real estate transaction.

A failing septic system might require immediate repairs or even a full replacement with a new system. Otherwise, it could release untreated sewage, contaminating groundwater, harming the environment and posing health risks.

If you’re selling your home, a prospective buyer might:

• Decide not to purchase

• Try to negotiate a lower price

• Ask you to repair or replace the septic system

Catching problems early on with an inspection may save you money and hassle later on.