In June 1889 Bishop Wordsworth announced his intention to build and endow a grammar school, perhaps seeking to emulate earlier churchmen who had founded famous schools. At this time there was dissension in the city as the local school board was dominated by Anglicans who would not build any board schools. There was also criticism of the bishop because he said that he did not want working class boys in the school. The school was completed in April 1890 and the original fees were very low. Fees were £1.10.0d. (£1.50) and boarding, including fees, was £9 per term. There was insufficient money to run the school, despite personal donations from the bishop and others, and an appeal was made to parents in 1894 to increase the fees to £2. A trust for the school was created in 1898 but inadequate funding dogged the school for many years.
Between 1902 and 1927 the school provided education for an increasing number of girls. In 1905 the school became a grammar school with a preparatory department. The opening of the South Wilts Grammar School for Girls in 1927 meant that Bishop Wordsworth's became a boys only school in that year. 1931 saw a financial crisis which resulted in more money being obtained and a building programme started. This included a hall, science laboratories and a library.
By the 1930s the school had achieved a reputation for pioneering educational work and in 1936 acquired public school status. The school was an aided school but in 1948 the Governors accepted voluntary controlled status. At that time it was described as 'the public school within the state system'. In 1955 the school numbers were 530 boys. In 1972 during local education authority re-organisation the school became a selective grammar school. Nowadays some 6th form classes are taught jointly with the 6th form at South Wilts Girls' Grammar School. Pictured here is part of the Upper School at 11 The Close. In 2002 there were 789 pupils aged between 11 and 18.