A Sewer Backup Endorsement to Your Homeowners or Renters Insurance Can Save You Money Later

In most cases, you can protect yourself from this “freak” event with an optional add-on for less than $50 per year

August 6, 2025

Few homeowners or renters realize that raw sewage seeping into basements, laundry rooms, or bathrooms typically isn’t covered under a standard policy. Without a sewer backup endorsement, you’ll pay out of pocket for cleanup, repairs, and even temporary housing, costs that often range from $10,000 to $50,000 or more. For an extra $7–$50 per year (depending on your home’s value and your insurer), that endorsement transforms an unthinkable disaster into a covered claim. Below, learn why sewer backups are excluded by default, what the endorsement covers (and doesn’t), how to add it, and why it’s one of the smartest, cheapest protections you can buy.

Why standard policies exclude sewer backups

Insurance companies draw a bright line between damage from a sudden burst pipe (covered under “water damage”) and raw sewage overflow, which they classify as a separate “flood” risk. Because sewage backups happen underground, in private sewer lines, shared street mains, or failing ejector pumps—the risk is difficult to quantify and extraordinarily expensive to remediate. By excluding it from basic policies, insurers can keep base premiums low, shifting the cost of this niche hazard to policyholders willing to pay a small surcharge for the endorsement.

How much does a sewer backup endorsement cost?

Rates vary by insurer, home value, and ZIP code, but typical annual premiums run:

$7–$15 per year for homes valued under $200,000
$15–$30 per year for homes valued $200,000–$400,000
$30–$50+ per year for homes over $400,000

Ask your agent for a quote, often adding the rider raises your total premium by under 5%. Compare that to a single sewer backup cleanup estimate, which typically starts at $10,000 and can exceed $50,000 when structural repairs and contents replacement are factored in.

Typical coverage limits and sublimits

When you add the sewer backup endorsement, your policy may impose separate sublimits. Common structures:

$10,000–$25,000 for sewage cleanup and structural restoration
$5,000–$15,000 for contents replacement (furniture, clothing, personal items)
$1,000–$5,000 for additional living expenses (hotel, meals, laundry) while repairs occur
No deductible for some insurers, or a small flat deductible ($250–$500) specifically for sewer backups

Verify your exact limits and deductible structures to ensure they meet your risk tolerance and home value. You can often increase sublimits for an additional premium.

What’s covered by the sewer backup endorsement

Raw sewage removal: Professional pumping, sanitizing, and disposal of contaminated water and solids.
Demolition & debris removal: Gutting affected drywall, flooring, cabinetry, and insulation.
Structural repairs: Rebuilding walls, subfloors, trim, and reinstalling fixtures to building code.
Contents replacement: Clothing, electronics, furniture, toys, keepsakes ruined beyond cleaning.
Deodorization & sanitization: Ozone or fogging treatments to eliminate odors and pathogens.
Additional living expenses: Hotel stays, meals, and laundry while your home is uninhabitable.
Plumbing line repair: Locating and fixing the clogged or collapsed private sewer line.
Ejector pump failure: Repair or replacement of a malfunctioning sewer ejector or sump pump.
Preventive measures: Coverage may include post‐loss backflow valve installation to reduce future risk.
Code upgrade coverage: Paying for required local code updates if replacement systems must meet current standards.

What’s NOT covered

Damage to municipal sewer mains or public sidewalks, those are the city’s responsibility.
Clogged toilets or sink drains inside your home not caused by seismic events or ground movement.
Regular maintenance, such as snaking or camera inspection of your private lateral line.
Damage from surface flooding (rainwater pooling), unless you also carry a flood policy.
Seepage through foundation cracks, this may require a separate “water backup” or foundation waterproofing warranty.
Intentional damage or neglect, such as failing to repair a known cracked pipe.

Backflow preventers vs. insurance endorsement

Installing a backflow prevention valve on your sewer line can reduce, but never eliminate—the risk of backups, as valves can fail or freeze. Insurance is the only way to guarantee financial protection. Even if your home has a backflow valve, most insurers still require the endorsement—and may offer a small premium discount if you install one. Treat the valve as your first defense and the endorsement as your financial safety net.

Adding the endorsement to your policy

To add sewer backup coverage:

Contact your insurance agent or log into your carrier’s online portal.
Request a “sewer backup endorsement” or “water backup and sump overflow endorsement.”
Review the proposed premium increase, deductible options, and sublimits.
Sign and pay the additional premium, often less than $5 per month.
Confirm the endorsement’s effective date in writing; it typically goes into effect immediately.

If you’re shopping carriers, be sure to compare not just base premiums but also the cost of endorsements and the limits/deductibles they offer.

Filing a claim: documentation & tips

If sewage backs up into your home:

Ensure safety: shut off electricity in the affected area and avoid contact with standing sewage.
Contact your insurer’s 24/7 claims hotline immediately.
Document the damage: take time-stamped photos and videos of flooded rooms, damaged belongings, and affected plumbing fixtures.
Keep receipts for any emergency expenses: hotel, meals, pump rental, or sewer-snaking fees.
Obtain written estimates from qualified remediation contractors and plumbers prior to repairs, if possible.
Retain contaminated contents, your insurer may inspect before disposal.
Provide your insurer with all documentation, then schedule remediation and repairs once you have a claims adjuster’s approval.

Real-world examples

In a 2024 North Carolina case, a Durham homeowner ignored minor backups until a heavy downpour overwhelmed her sewer lateral. Raw sewage flooded her basement, destroying her furnace, drywall, and family heirlooms. Cleanup and rebuilding totaled $38,000. Because she had purchased the $35/year sewer backup endorsement, her insurer covered 100% of costs . Without it, she would have faced a six-figure bill.

In another example, a Raleigh family had just installed a $400 backflow valve and believed they were protected. A faulty cap allowed debris to bypass the valve, flooding their laundry room. Their endorsement, just $20/year—covered $12,000 in cleanup and temporary housing costs. Both families say the endorsement was “the best $20 we ever spent.”

Cost–benefit analysis

Assume a $300 annual premium for a $250,000 home, and a $500 deductible on sewer backup claims. Over 10 years, you pay $3,000 in premiums. If you never file, that’s $3,000 for “peace of mind.” If you file a single claim costing $25,000, you pay only $500 out of pocket, saving $24,500. Even if you never experience a backup, the endorsement’s annual cost is far less than a single basement waterproofing project or sump pump installation.

Compare other “freak event” endorsements, service line coverage, identity theft protection, equipment breakdown—and you’ll find sewer backup often costs the least yet covers one of the priciest perils.

North Carolina resources

North Carolina homeowners can learn more about insurance endorsements and file consumer complaints with the North Carolina Department of Insurance. Renters should consult both their landlord’s policy and their personal renters policy to confirm eligibility for the sewer backup rider.

Bottom line

A sewer backup endorsement is inexpensive protection against one of the most devastating, and unhygienic—home disasters. While backups are rare, the financial and emotional toll of raw sewage in your living space can be crippling. For the price of a few coffee runs per year, you secure full coverage for cleanup, repairs, contents replacement, and temporary housing. Contact your insurer today to add the rider—because when it comes to sewer backups, you don’t want to be left holding the hose.