Hackworth was born in Wylam, that extraordinary hotbed of railway invention. He showed a natural inclination for mechanical construction and, on completing his apprenticeship, he took over his late father's post as blacksmith at Wylam colliery. There he became involved with experiments with steam locomotion.
In 1816 Hackworth reluctantly left Wylam because Sunday work offended his Methodist principles. After some time at Walbottle, he became locomotive superintendent as well as manager and contractor for the Stockton and Darlington Railway. Hackworth built a locomotive to his own design, the Royal George (1827), which was a marked advance on previous types and established the effectiveness of the steam locomotive. It had two vertical cylinders, with direct rod drive to cast-iron wheels, with shrunk-on tyres of wrought iron, the first of their type. Most importantly, it pioneered the discharge of exhaust steam through a converging nozzle blast pipe in the chimney, thus greatly increasing combustion intensity and steam production. The Royal George was well-suited to heavy coal traffic, but unsuitable for the task which the Stephensons envisaged - fast, long-distance transport of passengers and goods. In 1828 the initiative passed from Hackworth, and it was from the Stephenson works at Forth Street, Newcastle, that the true prototype of the modern locomotive rapidly emerged.
Hackworth served the Stockton and Darlington Railway Co. 1825-40, first as engineer, then as manager. During this time, he designed several successful locomotives.
In 1836 the Tsar decreed the first railway in Russia from St Petersburg to Pavlovsk. It was fully opened in 1839. It was an experiment, and had a 6' gauge. Bedlington Ironworks supplied some of the rails. The locos were supplied by Timothy Hackworth and Robert Stephenson (q.v.). The line was a great success. A replica of Hackworth's engine is kept in the Vitebsk Station in St Petersburg.
In 1840, Hackworth left to concentrate on his own Soho engineering business at Shildon, where industrial engines of all kinds were built, and where his house is now a museum. Hackworth, though not so well-known as some, was one of the great pioneers of the steam locomotive. It has been said, in fact, that no individual did so much for the improvement of the locomotive before 1830.