Replacing a Salem oil tank, or converting to gas: 2026 step-by-step

Why Salem homeowners are converting to gas in 2026

Conversion volume in Salem has roughly tripled over the past decade. Drivers behind the shift:

• 01NW Natural service area expansion. Coverage now reaches South Salem, NESCA, West Salem, Keizer, and most of the Marion County urban-growth boundary. Properties that were out of service area a decade ago are eligible today.
• 02Fuel cost. Residential heating oil in Salem ran $4.50 to $5.50 per gallon through much of 2024 to 2025. Natural gas equivalency was $1.80 to $2.40 per therm for similar heat output. The annual heating bill on a Salem rowhouse can drop $800 to $1,800.
• 03Reliability. Heating oil delivery scheduling, tank gauges that read wrong in cold weather, the inevitable mid-January out-of-fuel call. Gas is on-demand without homeowner monitoring.
• 04Insurance. Some Oregon insurers no longer renew homeowner's policies with active heating oil tanks. Conversion eliminates the issue.
• 05Resale. Properties with gas heat sell at slight premium vs equivalent oil-heat properties, particularly in the Salem-Keizer metro.
• 06Rebates and incentives. NW Natural and Energy Trust of Oregon offer combined incentives of $500 to $2,500 for conversions, plus additional rebates on high-efficiency gas furnaces.

NW Natural service area and the connection process

NW Natural is the natural gas utility for Salem-Keizer and most of western Oregon. Connecting service is more involved than turning on electricity but well-defined.

• 01Step 1: Confirm service availability. Salem-Keizer coverage is now nearly complete inside the urban growth boundary. NW Natural's online address-lookup tool confirms availability in 30 seconds.
• 02Step 2: Request a connection estimate. NW Natural sends a representative to the property to scope the line route from the street main to the meter location. Free.
• 03Step 3: Connection cost. Standard residential connection inside the existing main coverage runs $0 to $1,200 depending on distance from main and meter location. New service expansion (where main extension is required) can run $3,000 to $8,000+ but is often partially subsidized.
• 04Step 4: Connection scheduling. NW Natural typically schedules within 4 to 8 weeks. Peak fall demand (September to November) sometimes stretches to 10 to 12 weeks.
• 05Step 5: Inside work. Once the meter is set, a licensed plumbing/HVAC contractor handles the inside gas piping, furnace connection, and gas appliance hookups. This is separate from NW Natural's scope.

The full conversion sequence, step by step

A complete Salem-area oil-to-gas conversion has 6 phases. Total timeline is 6 to 12 weeks depending on permit and NW Natural scheduling.

• 01Phase 1: Pre-work planning (2 weeks). NW Natural service estimate, HVAC contractor walkthrough for gas furnace sizing, oil tank decommissioning quote, Energy Trust application.
• 02Phase 2: Oil tank decommissioning (2 to 4 weeks elapsed, 1 to 2 days on site). Permit, site survey, tank pump and clean, removal or abandonment in place, soil sampling, backfill. Full process here.
• 03Phase 3: NW Natural service connection (4 to 8 weeks elapsed). Schedules independently of the tank work; can run in parallel once the tank decommissioning is scheduled. Meter installed at the property.
• 04Phase 4: Inside gas piping (1 to 3 days). Licensed plumber/HVAC runs gas line from meter to furnace location, runs additional drops for gas range, dryer, or hot water if requested.
• 05Phase 5: New gas furnace installation (1 to 2 days). Remove old oil furnace, install new gas furnace, connect supply and return, ductwork modifications if needed.
• 06Phase 6: Decommissioning Report and final inspection (2 to 4 weeks elapsed). DEQ filing of the oil tank Decommissioning Report, final inspection of gas work by City of Salem or jurisdiction, NW Natural turn-on.

Removing the tank vs abandoning in place during a conversion

A gas conversion forces a tank decision but does not dictate the answer. You can remove the tank fully (excavate, lift out, dispose) or abandon it in place (pump, clean, fill with controlled low-strength material, leave in ground).

Both produce a Decommissioning Report and satisfy DEQ. The choice usually comes down to access, cost, and surface restoration:

• 01Remove if: Tank is accessible (clear yard, no driveway or addition over it), surface restoration is cheap (sod, gravel), you want the cleanest possible DEQ record. Typical Salem cost: $1,400 to $2,800.
• 02Abandon in place if: Tank is under a poured driveway or addition where excavation would require structural work, mature landscaping you want to preserve, or the homeowner just wants to be done with minimal yard disruption. Typical Salem cost: $1,100 to $2,200.
• 03Either way: Soil sampling is still required. Abandonment is not a way to skip the sampling.

What a full conversion costs in 2026 Salem

A complete oil-to-gas conversion runs $5,500 to $15,000+ in the Salem-Keizer market in 2026. Breakdown by component:

• 01Oil tank decommissioning: $1,100 to $2,800. Abandonment in place ($1,100 to $2,200) or full removal ($1,400 to $2,800). Detailed cost breakdown.
• 02NW Natural service connection: $0 to $1,500. Inside the urban core, often $0 (NW Natural absorbs as part of system expansion). New service expansion areas: $1,000 to $8,000+ (often partially subsidized).
• 03Inside gas piping: $800 to $2,500. Run from meter to furnace, plus optional drops for range, dryer, water heater. Depends on distance and complexity.
• 04New high-efficiency gas furnace: $3,500 to $7,500 installed. 95% AFUE units typical in the Salem climate. Higher-efficiency 97% units run $5,500 to $9,000.
• 05Old oil furnace removal: $200 to $600. Pump residual fuel from feed line, disconnect, haul off.
• 06Permits and inspections: $200 to $500. City of Salem mechanical/plumbing permits for the gas work, plus the oil tank decommissioning permit.

Subtract the rebates (next section) and the typical net Salem conversion cost in 2026 lands between $4,000 and $11,000. Most conversions pay back in heating-bill savings inside 5 to 8 years.

NW Natural and Energy Trust rebates that offset conversion cost

Several incentive programs apply to Salem-area conversions. Stacking them takes some coordination but adds up to significant savings:

• 01NW Natural conversion incentive: $500 to $1,000. Direct check from NW Natural for residential customers converting from electric or oil to gas. Application filed by the homeowner or contractor.
• 02Energy Trust of Oregon furnace rebate: $300 to $750. Performance-based rebate on high-efficiency gas furnaces (95% AFUE minimum). Filed through a participating contractor.
• 03Energy Trust of Oregon weatherization rebates: $500 to $2,000. Available when conversion is paired with attic insulation, duct sealing, or window upgrades. Stack with the furnace rebate.
• 04Energy Trust of Oregon loan program. Low-interest financing for full conversion projects, repaid through the gas utility bill over 5 to 15 years.
• 05Federal tax credits. The Inflation Reduction Act provides tax credits on high-efficiency natural gas furnaces (the 25C credit). Typically $300 to $600 depending on the specific equipment.
• 06HOTIP for contamination cleanup if a release is found. If the oil tank decommissioning reveals contamination, up to $50,000 reimbursement through HOTIP. See the DEQ guide for HOTIP details.

Permits: coordinating the tank decommissioning and gas work

A conversion involves multiple permits across two or three jurisdictions:

• 01Oil tank decommissioning permit. City of Salem or Marion/Polk County. $120 to $250. Pulled by the licensed oil tank service provider.
• 02Gas piping permit. City of Salem mechanical/plumbing. $100 to $300. Pulled by the licensed gas contractor.
• 03Furnace installation permit. Same jurisdiction as the gas piping. Often combined with the gas permit. $50 to $150.
• 04NW Natural service connection. Not a homeowner permit; NW Natural handles its own utility permits for trenching to the meter.

A homeowner does not pull these permits directly; the licensed contractors do. But the homeowner is responsible for coordinating between the oil tank contractor and the gas/HVAC contractor so the sequencing works.

Replacing the oil tank with a new oil tank (instead of converting)

A small minority of Salem-area homeowners replace a failing oil tank with a new oil tank rather than converting. Reasons this still happens:

• 01Property is outside NW Natural service area. Rare in the Salem-Keizer urban growth boundary, but applies to some outer Marion and Polk County properties.
• 02Existing oil furnace is recent and high-efficiency. Replacing the tank only (rather than the full conversion to gas) preserves the furnace investment. Typical scope: decommission old tank, install new aboveground steel or fiberglass tank, transfer the supply line.
• 03Backup heat preference. Some Salem-area owners prefer redundant heating systems and want to keep oil heat as primary.

New tank installation cost: $1,800 to $3,500 for a 275-gallon aboveground replacement, plus the decommissioning cost for the old tank. Underground replacement is rare (most counties no longer permit new buried residential heating oil tanks in Oregon).

Timing a conversion: avoiding the winter heating gap

The single most common conversion mistake in Salem is starting too late in the year and getting caught between fuel sources when cold weather hits.

• 01Best window: April through August. Heat is not needed during the swap, NW Natural and HVAC contractor schedules are open, permit offices are not backed up.
• 02Acceptable window: September through October. Doable but requires good coordination and lead time. Aim to complete by mid-October.
• 03Hard window: November through March. Possible but stressful. Cold-weather scheduling delays compound, and a 1-week schedule slip becomes a 1-week heating-emergency window.