According to ‘A History of the County of Wiltshire’ (1), Silver Street was previously called Old Poultry (in 1424), and then Poultry Street alias Minster Street (in 1549).
‘Poultry’ would be a reference to the poultry market, which also gives its name to the Poultry Cross, which is at the southern end of Silver Street.
The name Silver Street is likely to be because at some stage it was occupied by silversmiths, or jewellers. This seems to be the case for Silver Street in Cambridge (2), and also for the Silver Street in London (3)
The other possibility for the derivation of the name ‘Silver Street’ is that it was used by the cutlery trade, for which Salisbury was famous – it was noted for:
The height of its steeple,
The pride of its people,
Its scissors and knives
And diligent wives
(4)

Silver Street 1950. Reproduced courtesy of Francis Frith. Click to buy
Footnotes
- ‘Salisbury: St Thomas’s parish’, A History of the County of Wiltshire: Volume 6 (1962), pp. 81-83. URL: http://www.british-history.ac.uk/report.aspx?compid=41785. Date accessed: 09 July 2008. [↩]
- Cambridge Historic Core Appraisal June 2006 – Silver Street – page 3 of 3 [↩]
- Silver Street, London [↩]
- Hilliam, D, A Salisbury Miscellany, (Gloucestershire, 2005), p. 69 [↩]
[...] Silver Street [...]
[...] building, on the corner of the High Street and Silver Street achieved some notoriety when Bill Bryson criticized it in his book Notes from a Small Island. He [...]