What NGK Spark Plugs (USA) makes

NGK Spark Plugs (USA), Inc., now operating as Niterra North America, Inc., is the North American arm of the Japanese ignition and sensor maker Niterra Co., Ltd. (formerly NGK Spark Plug Co., Ltd.). It designs, assembles, and distributes two product families under two long-standing brands. Under the NGK brand it supplies spark plugs across nickel, platinum, iridium, and ruthenium designs, plus glow plugs, ignition coils, and wire sets. Under the NTK brand it supplies oxygen and lambda sensors, exhaust gas temperature sensors, MAP and MAF sensors, and other automotive sensors and vehicle electronics. The company also carries the parent's technical-ceramics heritage, the material science that underpins both the insulators in a spark plug and the sensing elements in an oxygen sensor.

The US operation runs both an original equipment business and an aftermarket business. On the OE side it develops and supplies ignition and sensor parts on vehicle programs; on the aftermarket side it sells the same product lines through distributors and repair shops across North America. Manufacturing in the US centers on spark plug assembly and NTK oxygen sensor production, with the deep-drawn metal shells, ceramic insulators, and sensing elements assembled into finished parts at the Sissonville, West Virginia campus.

Ownership and history

NGK Spark Plugs (U.S.A.), Inc. was established in 1966 as a subsidiary of NGK Spark Plug Co., Ltd., which itself dates to 1936. A dedicated US manufacturing entity, NGK Spark Plugs Mfg. (U.S.A.), Inc., followed in 1976, and NTK Ceramics (U.S.A.), Inc. in 1978. US spark plug production began in Irvine, California in 1981, and the first US-made automotive oxygen sensors followed in 1982. The company opened its Sissonville, West Virginia campus in 1994 and began NTK oxygen sensor production there in 1995. A technical center opened in Wixom, Michigan in 1996 and expanded in 2005 to serve as US corporate headquarters.

In April 2023 the company formally became Niterra North America, Inc., mirroring the global parent's rename from NGK Spark Plug Co., Ltd. to Niterra Co., Ltd. The change signaled a broadened focus beyond spark plugs into sensors, vehicle electronics, and ceramics, while keeping the NGK and NTK product brands intact. Niterra Co., Ltd. is headquartered in Nagoya, Japan and is listed on the Tokyo and Nagoya Stock Exchanges. The US business is led by Michael Schwab, who became Chief Executive Officer in 2019 after more than three decades with the company, and Tracy Neil was appointed General Manager for North America and PAMA Region Communications in January 2025.

Manufacturing and locations

The Sissonville, West Virginia campus is the company's US manufacturing hub, home to the NGK spark plug and NTK oxygen sensor assembly plants. It opened in 1994 with about 90 permanent jobs and, by the time of a 2023 expansion, had grown to more than 500 full-time and 70 temporary positions. In June 2023, with West Virginia Gov. Jim Justice on hand, the company broke ground on an expansion adding roughly 75,000 square feet and about 30 jobs. Corporate headquarters and the technical center sit in Wixom, Michigan at 46929 Magellan Drive. The company also operates distribution facilities in Irvine, California and Chicago, Illinois; Irvine was the original US spark plug manufacturing site before that role consolidated. The Sissonville plant has held OSHA SHARP recognition, a US Department of Labor program for small and mid-sized worksites with strong safety and health systems.

Certifications and quality

As an ignition and sensor supplier to major automakers, NGK Spark Plugs (USA) operates to the automotive quality-management norms that OEM programs require, the IATF 16949 family of standards, and runs the PPAP and APQP disciplines that go with production-part supply. The specific certificate numbers and dates are not posted on the US site, so those quality-system claims are reported here as claims. What is documented is the Sissonville plant's OSHA SHARP status, an independently reviewed recognition of its workplace safety and health program.

Known customers

Most of a Tier-supplier's customer relationships are unnamed, but one set is on the public record through a US government source.

Beyond these documented programs, the company describes itself as an OE supplier of choice for nearly every manufacturer, a claim consistent with its position as one of the largest global spark plug and oxygen sensor makers. Those broader claims are the company's own.

Sourcing evidence

NGK Spark Plugs (USA) appears in US customs records with 5,177 sea shipments on record and its most recent shipment dated August 9, 2026, so the trade activity is current. The import pattern is distinctive: the top foreign suppliers are the parent's own global plants, NGK Spark Plug in Japan, NGK Spark Plugs Asia, Ceramica e Velas de Ignicao NGK do Brasil, and Kurabe Industrial in Vietnam. That is the signature of a US assembly and distribution operation inside a Japanese multinational, importing components and finished ignition and sensor goods from affiliated plants and finishing or distributing them domestically, rather than sourcing from an arm's-length supplier base. The customs shipping address on record is in the Sissonville/Charleston, West Virginia area, consistent with the manufacturing campus.

Coverage caveats: these are US ocean-freight records only. Air, truck, and rail movements do not appear, some records name freight intermediaries rather than manufacturers, and product categories come from declared manifest codes, which are noisy. Absence of a record is not evidence of absence, and intra-company import volume does not by itself indicate domestic value-add, which for this company is concentrated in the nearshored assembly and sensor production at Sissonville.

Frequently asked questions

What does NGK Spark Plugs (USA) make?

NGK Spark Plugs (USA), now Niterra North America, makes and distributes spark plugs, glow plugs, ignition coils, and wire sets under the NGK brand, and oxygen sensors, exhaust gas temperature sensors, and other automotive sensors and vehicle electronics under the NTK brand. US manufacturing centers on spark plug assembly and oxygen sensor production at its Sissonville, West Virginia plant.

Who owns NGK Spark Plugs (USA)?

NGK Spark Plugs (USA), Inc. is a wholly owned subsidiary of Niterra Co., Ltd. of Nagoya, Japan, formerly NGK Spark Plug Co., Ltd. The parent is listed on the Tokyo and Nagoya Stock Exchanges. The US subsidiary was established in 1966 and renamed Niterra North America, Inc. in April 2023.

Where is NGK Spark Plugs (USA) headquartered?

Its US corporate headquarters and technical center are in Wixom, Michigan, at 46929 Magellan Drive. Its US manufacturing campus is in Sissonville, West Virginia, and it operates distribution facilities in Irvine, California and Chicago, Illinois.

Who are NGK Spark Plugs (USA)'s customers?

An OSHA success story from the US Department of Labor documents Ford, General Motors, Chrysler, and Honda as customers of the company's Sissonville spark plug and oxygen sensor plant. The company also serves the independent automotive aftermarket through distributors and repair shops across North America.

How many employees does NGK Spark Plugs (USA) have?

Its Sissonville, West Virginia campus alone reported more than 500 full-time and 70 temporary positions in 2023. Estimates for the total US workforce range from roughly 330 to over 500 across its manufacturing, headquarters, and distribution sites. The company does not publish a single official US headcount.

Is NGK Spark Plugs (USA) the same as Niterra North America?

Yes. NGK Spark Plugs (U.S.A.), Inc. formally changed its name to Niterra North America, Inc. in April 2023, following the global parent's rename to Niterra Co., Ltd. The NGK and NTK product brands are unchanged and remain in use.

Last verified September 28, 2026. Is this your company? Request a correction.