In 1768 George III ordered the building of an observatory at Kew, in anticipation of the transit of Venus, which was to be seen in England in the following year. This 'King's Observatory' survived until 1841, when the government decided no longer to maintain it, and its contents were distributed to various institutions. In 1842 the British Association for the Advancement of Science established a 'Physical Observatory' in the building. A committee was formed to exercise general superintendence over the activities of the Kew Observatory, and an honorary superintendent was appointed.
In 1866 a close relationship was established with the Meteorological Office in respect of the superintendence and publication of meteorological observations, and this was further cemented in 1867 when Balfour Stewart, the Superintendent, became Secretary to the Meteorological Committee. It was arranged that the observatory should become the central laboratory for testing and verifying all the instruments used by the office's various stations, and that supervision of those stations should be exercised through the observatory's staff. From 1869 the observatory received a fixed annual grant from the office for its services to the latter.
When Stewart resigned in 1871 control of the observatory passed from the British Association to the Royal Society, which placed it in the charge of the Meteorological Committee which also controlled the Meteorological Office. In 1876 the work of supervising the meteorological stations was transferred to the office, the annual grant being accordingly reduced, and the Royal Society's Gassiott Committee became the Kew Committee, subsequently the incorporated Kew Observatory Committee.
In 1900 the observatory was transferred to the newly formed National Physical Laboratory, becoming its Observatory Department. In 1908 a separate observatory was established at Eskdalemuir to undertake magnetic work for which Kew was no longer suitable.
On 1 July 1910 control of meteorological and magnetic work at Kew and Eskdalemuir Observatories passed to the Meteorological Office, Kew becoming styled the office's Central Observatory. A financial contribution was, however, received from the National Physical Laboratory in respect of certain instrument testing work which continued to be undertaken at Kew by their staff until 1914 when it was transferred to new buildings erected for the purpose at Teddington.
The work of the Meteorological Office at the Kew Observatory came to an end in 1980 when meteorological observation there was reduced to once daily as part of the United Kingdom voluntary network, under arrangements agreed with the director of the Royal Botanic Gardens.