Suffolk Cesspool & Septic

Cesspool and septic grants in Suffolk County

Two grant programs run through one county application, and together they pay up to $45,000 toward replacing a cesspool or septic system with an innovative/alternative onsite wastewater treatment system — an I/A system. That is not a discount or a tax credit. It is money paid out on your project.

Verified as of September 16, 2026. We re-check these pages quarterly.

Verified as of September 16, 2026. We re-check these pages quarterly.

The two grants

HOW THE TWO GRANTS MEET ONE QUOTE Approved installer quotes $32,000 The county's own average for an I/A system is about $25,000, before engineering and design $24,000 New York State — 75%, capped at $25,000 $8,000 County SIP — ceiling $20,000 the percentage binds first the county reaches the balance Still yours, and not covered by either grant: permit fees, engineering and design, landscaping. What you are actually awarded is set by the county's grant eligibility memo, issued against your installer's quote.
Two grants, one application — and the state share is capped as a percentage before it is capped in dollars.
County SIPNew York State SSRP
Maximum$20,000 per property75% of eligible costs, capped at $25,000
Paid toThe approved installer, directlyThe approved installer, or you as a reimbursement
WhenAfter the installation is completeAfter the installation is complete
Reimbursement?No — the county pays the installerEither route

The County Septic Improvement Grant Program (SIP) is funded by the voter-approved Suffolk County Water Quality Restoration Act, the eighth-penny sales tax that took effect in 2025. The county reported in June 2026 that it had raised more than $67 million since inception, split between I/A installations and sewers after administration.

The New York State Septic System Replacement Program (SSRP) is state money that Suffolk administers through the same application. Note the shape of it: 75% comes first, and the $25,000 is a ceiling on top of that. On a small job the percentage binds long before the cap does.

How the two stack to $45,000 · The county grant in detail · The state grant in detail

Who can get it

At a minimum the property must be an existing residential home — single-family, two-family, or single-family with one accessory apartment — served by a cesspool or septic system that will be replaced, not connected to sewers and not within a proposed sewer area. You need a valid certificate of occupancy, a current town-issued property tax bill, taxes current with no liens or foreclosure, and a deed on file with the Suffolk County Clerk. New construction on a vacant lot is not eligible, and you must apply and be issued a grant before the system is installed.

The full eligibility checklist

How the money actually moves

The county does not hand you a check. You pick an installer from the County Approved Installer List, that installer quotes the job, and after the installation passes inspection the county pays the installer on your behalf. Your invoice drops by the grant amount. The state share can go the same way or come back to you as a reimbursement.

Why the approved installer list matters

What the grants do not cover

Permit application fees, engineering and design, and post-installation landscaping are yours. Town or village building permits and wetlands permits may be needed on top of the county health permit — your design professional identifies those. On the East End, the town Community Preservation Fund programs can reimburse some of them.

Town rebates on the East End

If your system is failing

Applications with a documented system failure are prioritized before all others. The county's published process scores completed applications on documented failure and priority area, then issues grants in that order. If you are pumping once or twice a year, the county's own deputy county executive has said a failure is probably on its way.

Failure goes first — and what counts as failure

Before you count on it

These are finite programs and the conditions are the county's, not ours. The county says it responds to applications in about a week. Contact the grants team directly on 631-852-5811 or at SepticGrants@SuffolkCountyNY.gov, and apply at suffolkcountyny.gov/septicgrants.

Verified as of September 16, 2026. We re-check these pages quarterly. The $20,000, $25,000, 75% and $45,000 figures and the eligibility conditions on this page were confirmed against Suffolk County's own Septic Improvement Program page and its 2026 homeowner process overview on that date. The county's own disclaimer applies: all of it is subject to change. Confirm current availability before counting on a number.

All work is performed by local licensed, permitted Suffolk County-approved installers.

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Tell us the address and whether you are on a cesspool or a septic tank, and we will come back with what the county and state grants would cover at that property.

All work is performed by local licensed, permitted Suffolk County-approved installers.