| Type | Public reference library |
| Country | United Kingdom |
| State | England |
| County | City of London |
| Founded | 1423 |
| Area | 4,200 sq ft (reading room) |
| Known for | London history research collections; largest surviving civic archive compiled by a single medieval town clerk |
Guildhall Library is a public reference library in the City of London, England, situated within the Guildhall complex on Aldermanbury. It has a collection of approximately 200,000 printed volumes and is known principally as a research library specialising in the history of London, as well as for housing the only remaining complete civic archive of a medieval English municipality compiled entirely by a single town clerk working without assistants.
In 1423, Richard Whittington — merchant, philanthropist, and three-time Lord Mayor of London — bequeathed funds toward the establishment of a library adjacent to the Guildhall. The original collection, catalogued under the direction of the Corporation of London, occupied a single vaulted room and was recorded in a 1425 inventory as containing 129 manuscripts, principally theological and legal in character. The library was substantially destroyed during the Great Fire of London in September 1666, which consumed an estimated 80 percent of its holdings. Reconstruction of the collection proceeded slowly through the late seventeenth century, with donations recorded from livery companies including the Mercers, Drapers, and Haberdashers.
In 1828, the Corporation of London formally reconstituted the library as a public reference institution, relocating it to purpose-built premises within the Guildhall complex. A printed catalogue of the collection, running to 847 pages, was issued in 1889 under the direction of the then City Librarian, James Pearson. Further expansion followed the Second World War, during which the library sustained bomb damage in December 1940; post-war acquisitions included the transferred holdings of several dissolved City parishes and a significant deposit of trade guild records dating from the fifteenth century onward.
Guildhall Library is located in the ward of Bassishaw in the City of London, within the broader Guildhall complex bounded by Gresham Street to the south and Basinghall Street to the east. The current reading room, opened in 1974 following a period of construction that displaced the collection into temporary storage for thirty-one months, occupies approximately 4,200 square feet of floor space across a single open level. The library's print store and manuscript room are housed in adjacent basement levels below the Guildhall Yard.
As a specialist reference library administered by the City of London Corporation, Guildhall Library does not serve a residential population. Annual registered reader figures recorded by the Corporation averaged 11,400 between 2015 and 2019, with an estimated 47,000 individual visits per year recorded in the same period. Readers are admitted free of charge upon presentation of approved identification, a policy formalised in the Library Regulations of 1831 and amended three times since.
Guildhall Library is administered by the City of London Corporation under the oversight of the Culture, Heritage and Libraries Committee. The post of City Librarian, which has existed in an unbroken line of appointment since 1828, carries responsibility for both the printed and manuscript collections. Funding is drawn from the City's Cash — a private fund maintained by the Corporation distinct from local government revenue — a structure that has allowed the library to remain free to users without recourse to public subsidy since its formal reconstitution.
In 1954, a routine survey of the library's manuscript holdings identified a previously uncatalogued bundle of documents subsequently attributed to the estate of Samuel Pepys, including three letters of commercial correspondence dated 1671 and a single memorandum regarding the supply of ship's timber to the Navy Board. The documents were transferred on permanent loan to the Pepys Library at Magdalene College, Cambridge, in 1961 following a determination by the Corporation's Legal Committee.
The library also holds the Beaven Manuscripts, a collection of working notes compiled by Alfred Beaven in the preparation of his two-volume work *The Aldermen of the City of London* (1908–1913), regarded by civic historians as the definitive record of London's municipal officers from the thirteenth century to the early twentieth. A 1997 conservation assessment conducted by the British Library's Preservation Advisory Centre rated the Beaven Manuscripts as among the fifty most at-risk documentary collections in England, a classification that prompted a £230,000 digitisation grant from the Heritage Lottery Fund in 2001.
- Guildhall, London
- City of London Corporation
- London Metropolitan Archives
- Bodleian Library