| Year | Detail |
| 1927 |
The company was founded by Edward V. Sundt in Chicago, Illinois, U.S., and patented the first small, fast-acting protective Fuse designed to prevent sensitive test meters from burning out. |
| 1939 |
The company established a new manufacturing facility in Chicago, U.S., to manufacture Fuse for the automotive and aircraft industries. |
| 1950's |
The company established a new manufacturing facility in Des Plaines, Illinois, U.S., to manufacture Television fuses, Automotive Fuse Blocks, Automotive Switches, and Automotive Relays. |
| 1960's |
The company established a new manufacturing facility in England and Des Plaines, Illinois, U.S. to manufacture MICRO Subminiature Fuse, PICO Subminiature Fuse which are used in Aerospace industry. |
| 1968 |
Littelfuse was acquired by Tracor Inc., a defense technology and services company in the U.S. |
| 1970's |
The company established a new manufacturing facility in Piedras Negras, Mexico to manufacture ATO (Autofuse) Fuse for Automotive industry, Littelites Indicator Fuses for Office Electronics and Gaming Systems industry. |
| 1980's |
The company established a new sales office in Singapore and new power lab in Illinois, U.S. to manufacture Nano Fuse, MINI Fuse, 2AG Fuse, FLAT-PAK Fuse. |
| 1987 |
Westmark Systems, a defense contractor company, acquired Littelfuse and Tracor. |
| 1990's |
Littelfuse opened 16 manufacturing, distribution, sales and engineering offices across 4 continents and a new sales office in Hong Kong, China and a engineering office in Yokohama, Japan. |
| 1999 |
Littelfuse acquired Harris Corp. |
| 2000's |
The company opened a manufacturing facility in Wuxi, China, and expanded its electronics manufacturing facility in the Philippines. |
| 2006 |
Littelfuse acquired SurgX, Song Long, Concord, and Catalina companies. |
| 2016 |
The company acquired ON Semiconductor, Menber's SpA, and PolySwitch companies. |
| 2018 |
Littelfuse acquired Monolith Semiconductor and IXYS Corporation companies. |
| 2021 |
The company acquired Hartland Controls company. |