In common with many grammar schools in England and Wales, Spilsby's was founded in 1550 under Royal Charter of King Edward VI and bore his name.

[1] In the terms of the original grant of November 1550, Katherine, Duchess of Suffolk and Charles Brandon and their heirs were to have the right to nominate and appoint the schoolmaster.

[3] In 1894 Lord Gilbert Heathcote-Drummond-Willoughby, 1st Earl of Ancaster and 25th Baron Willoughby de Eresby established a charitable trust to continue annual funding of the grammar school into the future.

In 2007 the grammar school building was reoccupied and now serves as the home of New Life Community Church, providing conference facilities and a youth club for 11- to 15-year-olds.

The Trustees decided this should take the form of special grants to the new Spilsby High School - now called the King Edward VI Academy.

The additional funding provided an audio and visual recording studio, enhanced ICT facilities and an archive area in a recently refurbished Humanities Block with interactive whiteboards and well resourced departments.

Only 22% of pupils achieved the equivalent of five or more GCSEs at grade C or above,[6] however the then King Edward VI Humanities College was the only bi-lateral educational facility in the published results table.

They are: The school badge depicts crossed corn sheaves in gold on a white and red shield, representing growth and a rich educational harvest while linking to Lincolnshire's rural and agricultural heritage.

In 2023, the school was accused by some parents of damaging children's mental health and breaching pupil's human rights.