During the First World War, the town was home to a major munitions plant owned by the British Chemical Company.

On January 1, 1998, Trenton was amalgamated with the Village of Frankford and the Townships of Murray and Sidney to form Quinte West.

Other large employers include Trenton Cold Storage,[3] Norampac, Kruger, Mapco, Citipack, Jobsters, Pentair Thermal Controls, Nestlé, ElectroCables, Domtech, Global Med Inc., Mckesson Canada and DECA Cables.

Tourism also plays an important role in the economy, given Trenton's location as the southern entry point for the Trent–Severn Waterway.

Hastings County Road 2 (formerly Ontario Highway 2) is the main east–west route through town, leading towards Brighton in the west and to Belleville in the east.

The main north–south route is Hastings County Road 33 (formerly Ontario Highway 33), leading towards Picton to the south and Stirling to the north.

Via Rail offers limited passenger service to and from Toronto, Ottawa and Montreal via Kingston to Trenton Junction station.

It features an original RAF Halifax Bomber, the 75th RCAF time capsule, a Lockheed CC-130E Hercules, and many other aircraft and exhibits.

Popular freshwater fish in the Bay of Quinte and the Trent River include walleye (pickerel), bass, pike, perch, and mudcat.

During particular times of the year, salmon and rainbow trout can be caught in the Trent River and in cold-water streams in the area.

In 1990, Canadian poet Al Purdy (who received the Order of Canada and the Governor General's award) published his only novel A Splinter In The Heart.

Purdy also wrote a poem entitled "At the Quinte Hotel" about the strip club in Trenton called The Sherwood Forest Inn.