After the build was complete, the lighthouse's illumination of 24 candles were first lit on 16 October 1759. While in use, Smeaton's lighthouse was 72 feet high, and had a diameter at the base of 26 feet (8 metres) and at the top of 17 feet (5 metres). It remained in use until 1877 when it was discovered that the rocks upon which it stood were becoming eroded: each time a large wave hit the lighthouse shook from side to side.
The upper part was dismantled and rebuilt as a memorial to Smeaton on a new base on Plymouth Hoe in 1882, replacing the triangular obelisk that had been built there by Trinity House as a navigation aid in the early 19th century. It was opened to the public by the Mayor of Plymouth on 24 September 1884.
The foundations and stub of the old tower remain on the Eddystone Rocks, close to the current lighthouse; the foundations proved too strong to be dismantled so the Victorians left them where they stood.