In 1802 a new universalist congregation was founded in Boston on the Universalist principles of ‘salvation for all’. In 1819 the present handsome Georgian meeting house was built to accommodate 250 people and the Unitarian congregation moved here from a chapel in Chapel Row.

Constructed from red-brick in Flemish Bond. It has ashlar quoins, plinth and dressings. The side walls are brown brick and there is a hipped slate roof with overhanging eaves on paired brackets. Two storeys, three-bay front, stone plinth with central double doors, with flush panels, and Gothic fanlight. Rear elevation has central ashlar plaque inscribed ‘Built MDCCCXIX’ and two round-headed Gothic sash windows.

A burial ground with monuments, including early 19th century table-tombs, survives to the rear of the chapel.

The hall (added in 1875) is used by local secular and religious groups.

On 7th June 2021 Boston Unitarians (Lincolnshire) completed the registration process for a license to conduct marriage ceremonies for same-sex couples, becoming the 99th Unitarian congregation to do so. Their minister, Rev Patrick Timperley, said:

“We are delighted that the Unitarian Meeting House is the first place of worship in the borough of Boston to be licensed for both same-sex and opposite-sex marriages. We are now looking forward to hosting weddings and other ceremonies in accordance with government regulations.”