What Littelfuse makes

Littelfuse is a diversified industrial technology manufacturer built around three product families: circuit protection, power control, and sensing. The company started in 1927 with a "little fuse" for the automotive industry, and fuses remain a core line, from miniature chip fuses to high-current and high-voltage fuses and resettable PPTC devices. Around that core it makes a broad protection portfolio: gas discharge tubes, TVS diodes, varistors, polymer ESD suppressors, and thyristors.

The power-control side has grown through acquisition into power semiconductors, including silicon and silicon-carbide diodes and thyristors produced at a 200mm wafer fab in Dortmund, Germany. The electromechanical range covers relays, switches, circuit breakers, and protective and monitoring relays. On the sensing side, Littelfuse supplies automotive and commercial-vehicle sensors, temperature sensors, switches, and electronic modules. The company reports three segments: Electronics, Transportation, and Industrial. As a diversified electronics component maker it sells both to Tier 1 suppliers and directly to OEMs across automotive, industrial, and consumer electronics.

Financial performance

Littelfuse is publicly listed on NASDAQ under the ticker LFUS. For fiscal 2025, ended December 27, 2025, the company reported net sales of $2,386.3 million, up 9% from $2,190.8 million in fiscal 2024. Adjusted operating margin was 15.2% and adjusted diluted earnings per share were $10.68, up 34% year over year.

GAAP results for 2025 look different from the operating picture because of a roughly $301 million non-cash goodwill impairment charge tied to the Semiconductor Products business. That charge pulled the GAAP operating margin down to 1.6% and produced a GAAP net loss of $71.7 million for the year. The impairment is an accounting write-down of prior acquisition value, not a cash outflow or a solvency event. By segment, fiscal 2025 net sales were $1,345.5 million in Electronics (up 13.4%), $676.4 million in Transportation (up 0.6%), and $364.4 million in Industrial (up 9.9%). The balance sheet is conservative: about $563.4 million in cash against $802.6 million of total debt at year-end, for net debt near $239 million.

Ownership and history

Littelfuse was founded in 1927 in Chicago and has grown into a company of roughly 16,000 associates with more than 40 sales, distribution, manufacturing, and engineering facilities across the Americas, Europe, and Asia, operating in over 20 countries. It is widely held on NASDAQ with no single controlling parent. The corporate headquarters moved in 2024 to a leased office at 6133 N River Rd in Rosemont, Illinois, a suburb near Chicago O'Hare; older references that list a Chicago address predate the move.

Recent corporate activity has centered on the power-semiconductor and industrial businesses. In December 2024 Littelfuse completed the purchase of a 200mm wafer fab in Dortmund, Germany from Elmos Semiconductor for about 94 million euros, adding wafer capacity for power devices. In February 2025, Dr. Greg Henderson became President and Chief Executive Officer, succeeding David Heinzmann, who retired after roughly 40 years with the company; Henderson previously led Analog Devices' Automotive and Energy, Communications, and Aerospace Group. In December 2025 the company completed the acquisition of Basler Electric Company, a maker of electrical control and protection solutions with annualized sales of about $130 million, for $350.3 million.

Certifications and quality

Littelfuse states that it maintains ISO and IATF certifications across its manufacturing network. The primary automotive quality standard is IATF 16949:2016, and the company holds current IATF 16949 certificates at multiple sites. Public certificates issued by Intertek cover, among others, Littelfuse Semiconductor in Wuxi (design and manufacture of TVS diodes, thyristors, and SIDACtors, valid to July 2027), Suzhou Littelfuse (miniature fuse links and sensors, valid to June 2027), Littelfuse Philippines (chip fuses, wire-in-air fuses, and ESD protection devices, valid to April 2027), and the commercial-vehicle products plant in Muzquiz, Mexico (switches and accessories, valid to April 2027). Automotive supply to OEM and Tier 1 programs typically requires this standard alongside PPAP and advanced product quality planning discipline, which multi-site IATF certification supports.

Known customers

Littelfuse sells components into automotive, industrial, and electronics supply chains rather than a small named account list, and it does not disclose a customer roster in its public filings. No individual OEM program is documented on the public record at a level that clears the evidence bar, so this profile does not name specific customers.

Sourcing evidence

US customs records show a large, active import footprint for Littelfuse's distribution arm. The primary US importer entity of record, "Littelfuse Far East," based in Eagle Pass, Texas, has more than 7,100 sea shipments on file, with the most recent dated September 21, 2026. The named shippers are dominated by Littelfuse's own overseas subsidiaries, including Suzhou Littelfuse and Dongguan Littelfuse Electronics, alongside third-party component makers such as Jenn Feng Electric Industrial and Shin Chin Industrial.

The reading here is intra-company sourcing, not a third-party supply base: a global manufacturer moving finished and semi-finished product from its own Asian plants into a US distribution point, plus some outside component buys. That pattern is normal for a vertically integrated components company and says more about internal logistics than about outside vendor dependence. For buyers weighing tariff exposure and nearshoring options, the relevant fact is that Littelfuse manufactures across Asia, Europe, the Americas, and Mexico rather than from a single region.

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.

Frequently asked questions

What does Littelfuse make?

Littelfuse makes circuit protection, power control, and sensing components. That includes fuses and resettable fuses, TVS diodes, gas discharge tubes, varistors, power semiconductors such as diodes and thyristors, relays and switches, and automotive and industrial sensors. It reports three segments: Electronics, Transportation, and Industrial.

Who owns Littelfuse?

Littelfuse is a publicly traded company listed on NASDAQ under the ticker LFUS, with no single controlling parent. It was founded in 1927 and is headquartered in Rosemont, Illinois.

What is Littelfuse's annual revenue?

Littelfuse reported net sales of $2,386.3 million for fiscal 2025, up 9% from $2,190.8 million in fiscal 2024. Its fiscal 2025 adjusted operating margin was 15.2% and adjusted diluted EPS was $10.68.

Where is Littelfuse headquartered?

Littelfuse is headquartered at 6133 N River Rd, Suite 500, Rosemont, Illinois, a Chicago suburb near O'Hare. It moved there in 2024 and operates more than 40 facilities across over 20 countries.

Who is the CEO of Littelfuse?

Dr. Greg Henderson has been President and Chief Executive Officer since February 2025. He succeeded David Heinzmann, who retired after roughly 40 years with the company. Henderson previously led Analog Devices' Automotive and Energy, Communications, and Aerospace Group.

What certifications does Littelfuse hold?

Littelfuse maintains ISO and IATF certifications across its manufacturing network. It holds current IATF 16949:2016 automotive quality certificates at multiple sites, including plants in Wuxi and Suzhou (China), the Philippines, and Muzquiz (Mexico), all issued by Intertek.

Last verified September 27, 2026. Is this your company? Request a correction.