There are no surviving records documenting when a mill was first built on the current site, but it is recorded as being a corn mill in 1086 in the Domesday Book. In 1289, the mill was used for fulling, removing oil and other impurities from cloth and textiles. The mill had become a paper mill by 1774. The world's first mechanised paper machine was established at Frogmore mill in 1803 by Sealy and Henry Fourdrinier with assistance from Bryan Donkin. This machine allowed continuous automated production of paper rolls. Unfortunately the £60,000 costs of the paper machine meant that the Fourdrinier brothers were bankrupted by 1810.
For most of the 19th century, the mill was owned by the Grand Junction Canal, predecessor of the Grand Union Canal. In 1851, the chemical production of paper from wood (now known as soda pulp), used in newspapers, began at the mill. From 1853 to 1887 the mill was linked to Two Waters Mill, also near Hemel Hempstead. In 1890, the British Paper Company was founded and took over operations at the mill; it fully purchased the premises in 1929.
The mill is now run by The Apsley Paper Trail, a charitable organisation, and operated as a visitor, education and community use centre. Eleven full-time staff are employed at the mill. It has been used for various theatrical productions, including the rock musical Rent.