Wallingford was established on October 10, 1667, when the Connecticut General Assembly authorized the "making of a village on the east river" to 38 planters and freemen. The “long highway” located on the ridge of the hill above the sandy plain along the Quinnipiac River is the present Main Street in Wallingford. On May 12, 1670, Wallingford was incorporated and about 126 people settled in the town. Six acre lots were set out and by the year 1675, 40 houses stretched along today's Main Street. In 1775 and again in 1789, George Washington passed through Wallingford.

During the nineteenth century, Wallingford industry expanded with a considerable concentration of small pewter and Britannia ware manufacturers. By mid-century, Robert Wallace acquired the formula for nickel silver and established with Samuel Simpson, R. Wallace & Company the forerunner of Wallace Silversmiths. It was also during this period that many of the small silver and Britannia plants were combined to form the International Silver Company with its headquarters in Meriden, Connecticut and several plants in Wallingford.

In October, 1871, Wallingford's train station was completed for the New York, New Haven and Hartford Railroad. Noted for its mansard roof, ornamental brackets and stone quoins — the interlocking exterior corners — the station is among the few remaining of its kind that were built during President Grant's administration at the height of railway expansion. The town undertook an overhaul to the roof and exterior with the help of state and federal grants in the early 1990s. The station is served by the Northeast Regional route of Amtrak.

Wallingford was the birthplace of Aaron Jerome (1764-1802), the great-great-grandfather of Sir Winston Churchill; inventor and publisher Moses Yale Beach (1800–1868), who would go on to found the Associated Press; singer Morton Downey; conservative talk show host Morton Downey, Jr. (1932-2001); and Georgia governor and signer of the Declaration of Independence Lyman Hall. It was also the childhood home of World War I flying ace Raoul Lufbery. The town produces its own electricity and maintains an electric company with rates well below the state's average.

• East Wallingford
• Quinnipiac (partly in North Haven)
• Tracy
• Wallingford Center
• Yalesville

Wallingford is home to the Choate Rosemary Hall school (which graduated John F. Kennedy, John Dos Passos, Glenn Close, Jamie Lee Curtis, Michael Douglas, Bill Simmons, and Adlai Stevenson).

Public High Schools - Lyman Hall High School, Mark T. Sheehan

Public Middle Schools - Dag Hammarskjold (also named New England Spotlight School), James H. Moran

Public Elementary Schools - Rock Hill, Pond Hill, Moses Y Beach, Cook Hill, Parker Farms, Yalesville, Evart C. Stevens, Highland

Pariochial Schools - Holy Trinity