What septic repairs cost

Published national ranges for common septic repairs, from baffles, pumps and filters to risers, lids and drain fields, with what each part does.

Updated October 18, 202614 official sources

On this page6 sections

1What common septic repairs cost
2What drain field work costs
3What each part does
4When the drain field is the problem
5Prices we don't give
6What to ask before work starts

The figures here are published national ranges from cost guides. They aren't quotes. Use them to plan, then ask septic companies near you to look at the system and price the repair.

What common septic repairs cost

Repair	Published range
A typical septic repair	$600 to $3,000 per job^1-3
A baffle repaired or replaced	$250 to $900 per job^1-3
A pump repaired or replaced	$250 to $1,500 per job^1-3
A distribution box replaced	$500 to $1,500 per job^{1, 3-4}
Cleaning the effluent filter on its own	$100 to $200 per job^5-6
A new effluent filter	$200 to $300 per job^{1-2, 6}
A riser, installed	$200 to $600 per riser^{1, 4, 7}
A new tank lid	$150 to $600 per job^1-3

What drain field work costs

Job	Published range
Drain field repair or rejuvenation	$1,000 to $5,000 per job^{3, 8}
A conventional drain field, replaced	$3,000 to $15,000 per field^7-10
A mound drain field	$10,000 to $20,000 per field^8-9

What each part does

The tank. It holds wastewater long enough for solids to settle to the bottom as sludge while oil and grease float to the top as scum. Compartments and a T-shaped outlet keep the sludge and scum from leaving the tank for the drain field.¹¹ EPA says a concrete tank may last 50 years or more.¹⁰
Baffles. A tank needs a baffle at the inlet and at the outlet, to keep the scum layer and suspended particles from flowing out with the wastewater into the drain field.¹²
The effluent filter. Fitted at the outlet, it catches solids before they can leave the tank and clog the drain field.¹² NC State Extension says a filter needs checking and servicing about every 2 to 3 years.¹³
The distribution box. Also called the D-box, it sits underground between the tank and the drain field and spreads the tank's effluent evenly into the field's pipes.¹²
The pump. Not every system has one, but where yours does, EPA says many pumps and controls need replacing every 10 to 20 years.¹⁰
Risers and lids. A riser brings the tank's access port up to the soil surface, to make future cleaning and inspection easier.¹⁴

When the drain field is the problem

The drain field delivers the liquid from the tank to the soil, where the real treatment happens.¹³ Penn State Extension calls it the most expensive and difficult part of a septic system to correct or replace.¹²

EPA says that in a drain field more than 25 to 30 years old, the layer that forms at the bottom of the trenches can thicken and reduce the field's ability to take the wastewater, which can cause ponding, untreated wastewater on the surface or backups into the house.¹⁰ Pumping the tank won't bring back a field whose soil is completely clogged: NC State Extension says that by then a new drain field, an advanced pretreatment unit or both is usually needed.¹³

Prices we don't give

Installing a tank alarm. Only one cost guide prices it, so there isn't a range we can stand behind.
An emergency or after-hours rate. None of the cost guides gives a dollar figure for one.

What to ask before work starts

What the company found, and which part it thinks has failed: the tank, a baffle, the pump, the distribution box or the drain field.
Whether the tank will be pumped first, and whether that's in the price.
Whether the price includes any permit the repair needs.
For a new pump or filter, what warranty comes with it.

If you're not sure what's wrong yet, read signs your septic system is failing.

Each company on this site is listed with its phone number where it has one, so you can call two or three and compare. You can also use the request form to reach septic companies near you.

Ranges compiled from HomeGuide, Angi, HomeAdvisor, Fixr and the US EPA; how the parts work from the US EPA and Penn State and NC State Extension, checked October 2026.