Oil Tank Costs on Long Island, Job by Job
Most Long Island oil-heated homes have one 275-gallon steel tank in the basement or garage. Larger and older homes often have two tied together, and many houses built before the 1980s had a buried tank in the yard that may or may not still be there. Here's what each job typically costs in 2026:
| Job | Typical Cost | Notes |
|---|---|---|
| Replace 275-gal above-ground tank (single wall) | $1,500 – $2,500 | Old tank pumped, cut and hauled; new tank set and connected |
| Replace with a double-wall or 'tank-in-tank' unit | $2,500 – $3,500 | Built-in leak containment; often preferred by insurers |
| Two-tank setup (2 × 275 gal) replaced | $3,000 – $5,500 | Common in larger homes and older colonials |
| Remove above-ground tank, no replacement | $300 – $800 | After a switch to gas or a heat pump |
| Buried tank: abandon in place | $2,000 – $3,500 | Pumped, cleaned, filled with sand or foam, documented |
| Buried tank: excavate and remove | $3,000 – $5,000+ | Depends on size, depth, and what's built over it |
| Soil testing (if contamination is suspected) | $400 – $1,500 | Lab samples from the excavation |
| Contaminated soil cleanup | Can exceed $10,000 | Rare, but the reason to deal with old buried tanks early |
What moves the price: getting the old tank out (a basement tank usually has to be cut up to fit through the bulkhead or stairs), rerouting the fill and vent pipes to meet code, the tank itself (double-wall tanks cost more but contain a leak), and any oil left in the old tank, which is usually pumped and transferred to the new one.
Signs Your Oil Tank Needs Replacing
Weeping or wet spots on the bottom seam
Tanks usually rust through from the inside out, where water collects at the bottom. A damp seam or a drip pan with oil in it means the tank is near the end.
Rust scale, blistered paint or soft spots
Surface rust is cosmetic. Flaking scale or a spot that dents under a screwdriver is not.
Oil smell in the basement
A tank, filter or fitting is leaking somewhere. Get it found before it soaks into a slab or the soil.
Rusted or bent legs
A full 275-gallon tank weighs about a ton. Corroded legs are a tip-over risk.
Water or sludge at the burner
Repeated clogged filters and nozzles can come from a tank that is shedding rust and holding water.
A tank over 25–30 years old
Many insurers and buyers ask about tank age. An old single-wall tank can be a negotiating point in a sale.
Nassau County Oil Tank Rules
In Nassau, the contractor removing or abandoning a tank files a Tank Abandonment/Removal Notification Form with the Nassau County Department of Health at least seven days before the work, and the county schedules removals on weekdays. Many incorporated villages (Malverne, Lynbrook, Upper Brookville and others) also require their own permit first, and some ask for photos and disposal receipts afterward. Ask your contractor to handle both filings and give you copies. You will want them when you sell.
Suffolk County Oil Tank Rules
Suffolk regulates tanks under Article 12 of the Suffolk County Sanitary Code. Fuel oil tanks under 1,100 gallons used to heat the home on site are generally excepted from county registration (outside the special groundwater areas covered by Article 7), which covers nearly every residential tank. That exception doesn't mean anything goes when a tank is retired: an out-of-service tank still has to be closed the way Article 12 describes, and towns such as Islip and Southampton want the contractor's closure certificate filed with the building department.
Suffolk County has also offered homeowners a $100 incentive for closing residential tanks of 1,100 gallons or less in line with Article 12, paid on proof of the closure. Some towns run their own tank programs too. Check with the Suffolk County Department of Health Services and your town building department for what's currently available.
New York State's petroleum bulk storage registration generally applies to tanks over 1,100 gallons, so a typical 275–550 gallon home setup is handled at the county and town level rather than by the state.
Buried Tanks: Abandon in Place or Dig It Out?
Abandoning in place means pumping the tank, cleaning it, filling it with sand or inert foam, and capping the lines. It's cheaper and doesn't tear up the yard, and it's the usual choice when a tank sits under a driveway, deck or addition.
Excavating costs more but leaves nothing behind, and it lets you see the soil around the tank. Some buyers and lenders prefer it. Either way, if there's staining, odor or wet soil around the tank, expect soil samples. Most old tanks come out clean, but contamination is the reason not to leave a 40-year-old buried tank sitting there.
Replace the Tank, or Get Off Oil?
If your tank and your boiler are both getting old, price both paths before you spend $2,000+ on a new tank:
- ✓Gas on your street? An oil to gas conversion removes the tank for good. See also how to get a gas line to your house, since the free 100-foot rule is ending.
- ✓No gas main? A whole-home cold-climate heat pump can replace oil heat, and PSEG Long Island pays a flat rebate for it. See our Long Island heat pump rebate guide.
- ✓Staying on oil? Pair the new tank with a yearly oil burner tune-up. A clean filter and nozzle keep the new tank's fuel moving.