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Subterranean Termite Treatment in Ontario, CA
High subterranean risk from agricultural soil history and irrigation.
Ontario's soil conditions make it particularly susceptible to subterranean termites — Termidor treatment creates a continuous liquid barrier around your foundation that eliminates existing colonies and prevents new ones.
Subterranean Termite Treatment — Quick Facts
Price Range
$800–$2,500
Duration
1 day
Warranty
3+ years
Vacating Required
No — stay in your home
Best For
subterranean termites
Chemical Residual
Minimal — EPA-registered materials
Why Subterranean Treatment in Ontario?
High subterranean risk from agricultural soil history and irrigation.
San Bernardino County's soil conditions — including irrigation-heavy landscaping, clay soil, and former agricultural use — create ideal subterranean termite habitat. Termidor's transfer effect means it eliminates not just exposed workers but the entire colony, including the queen.
All subterranean termite treatment services in Ontario are performed by our CA-licensed inspector (License #PR7791) and come with a written report, warranty documentation, and a free inspection before any treatment is recommended.
Inland valley homes often have subterranean termite activity driven by irrigation systems, lawn watering, and moisture-retaining clay soils. Termidor creates a continuous treatment zone that intercepts foraging termites before they reach wood structural members.
Peak termite swarm season in Ontario: March–May. Don't wait for visible damage — early treatment costs a fraction of structural repairs.
Inspector Note — Ontario
“Historic Ontario homes near Euclid Avenue often have original citrus-era irrigation channels converted to drainage beneath the property — these channels maintain chronic soil moisture and require special attention during the subterranean assessment.”
What to Expect: Subterranean Termite Treatment in Ontario
Here's exactly what happens from your first call through completion.
Inspection & Mapping
We identify all mud tubes, entry points, and active colonies around your foundation. A treatment map ensures complete perimeter coverage with no gaps.
Trenching
A trench is dug along the exterior foundation. Where concrete slabs or patios are present, holes are drilled at regular intervals for sub-slab injection.
Termidor Application
Termidor (fipronil) is applied at labeled rates into the trench and/or through drilled ports, creating a continuous treatment zone through the soil around your home.
Backfill & Monitoring
Trenches are backfilled. Termidor transfers through the colony via contact, typically eliminating it within 90 days. Annual inspections maintain your long-term warranty.
Subterranean Termite Treatment: Pros & Cons
Advantages
- Eliminates entire colony — not just visible termites
- Long-lasting protection: 3–10+ years with annual monitoring
- No vacating required — you stay home during treatment
- Termidor is the #1 subterranean termite treatment trusted by pest professionals
Limitations
- Does not treat drywood termites (separate treatment required)
- Some drilling required where concrete covers foundation perimeter
- Requires annual inspection to maintain warranty
- Termidor leaves a soil residual (not appropriate for certified organic properties)
Why Ontario Homeowners Choose Ultimate Termite
Local Expertise
Based in Orange County — we know Ontario's housing stock, local termite pressure, and the specific conditions that drive infestation in San Bernardino County.
CA License #PR7791
Fully licensed by the California Structural Pest Control Board. All inspections and treatments are performed by credentialed professionals.
Free Inspection First
Every subterranean termite treatment job in Ontario begins with a free whole-structure inspection. You get a written report and price — no obligation.
All 8 Treatment Methods
We offer every proven treatment method including fumigation, heat, orange oil, Termidor, and spot treatments — so we recommend what's right, not what's most profitable.
Senior & Military Discounts
We proudly offer discounts for senior homeowners and active or retired military families throughout Southern California.
Written Warranty
All subterranean termite treatment work in Ontario includes a written warranty. If covered activity returns during the warranty period, we come back at no charge.
Other Termite Services in Ontario
We offer all 8 treatment methods in Ontario. After a free inspection, our licensed inspector recommends the right approach for your infestation.
Subterranean Termite Treatment in Nearby Cities
We provide subterranean termite treatment throughout San Bernardino County and all of Southern California.
Frequently Asked Questions
How much does subterranean termite treatment cost in Ontario?
Subterranean Termite Treatment in Ontario typically costs $800–$2,500. The exact price depends on the size of your home, the extent of infestation, and accessibility. We provide free on-site inspections with a no-obligation written estimate before any work begins.
How long does subterranean termite treatment take in Ontario?
Subterranean Termite Treatment in Ontario takes approximately 1 day. You do not need to leave your home during treatment. We schedule promptly and work around your availability.
Is subterranean termite treatment the right choice for my Ontario home?
Subterranean Termite Treatment is best suited for subterranean termite problems. Ontario homes commonly face subterranean termite risk from soil moisture and irrigation. After your free inspection, our licensed inspector will confirm whether this is the right treatment for your specific situation.
Do you offer subterranean termite treatment throughout all of Ontario?
Yes — Ultimate Termite serves all neighborhoods in Ontario and the surrounding areas of San Bernardino County. Whether you're near the center of Ontario or on the outskirts, we can schedule a free inspection and treatment promptly. Call (714) 240-2800 or schedule online.
How long does Termidor take to work?
Termidor transfer technology means the colony is typically eliminated within 90 days. You may still see some termite activity for several weeks while the product works through the colony.
Do I need to leave my home during treatment?
No — Termidor is applied in the soil around the exterior of your home. No interior disruption or vacating is required.
How long does the treatment last?
Termidor provides 3–10+ years of protection. Annual inspections are required to maintain the warranty and to identify any new activity early.
What if I have a concrete slab foundation?
We drill through concrete at the required intervals to inject Termidor beneath the slab and along the foundation perimeter. Holes are filled after treatment.
Schedule Subterranean Termite Treatment in Ontario
Free inspection — no obligation. CA License #PR7791. Senior & military discounts available.