In 1863 Walcott was appointed precentor (with the prebend of Oving) of Chichester Cathedral, and held that preferment until his death.
Always at work on antiquarian and ecclesiological subjects, he was elected Fellow of the Society of Antiquaries of London on 10 January 1861.
Walcott contributed articles to periodicals and to the transactions of learned societies, and he was one of the oldest contributors to Notes and Queries His separate works include: Walcott contributed to Henry Thompson's collection of Original Ballads, 1850, and to the Rev.
He edited in 1865, with additions and notes, Thomas Plume's Account of Bishop Hacket, and published, with William Archibald Scott Robertson in 1872 and 1874, two parts of Parish Church Goods in Kent.
Many of his papers on the inventories and registers of ecclesiastical foundations were also issued separately, and he presented manuscripts to the British Museum.