William Borrer (13 June 1781 – 10 January 1862), F.R.S. was an English botanist noted for his extensive and accurate knowledge of the plants of the British Islands. Many important works on British botany during the early 1800s acknowledged his assistance. In 1813 he began with Dawson Turner a work on British lichens, which was finally published in 1839. He contributed numerous other writings on English botany. Borrer was a patron of the sciences and interested himself in the education of the poor. He died at his residence at Barrow-hill, Sussex.