Click place name to go to the list of private investigators operating in that area.
- Salford
- Salisbury
- Scarborough
- Scotland
- Scotland, South West
- Scunthorpe
- Sevenoaks
- Sheffield
- Shipley
- Shrewsbury
- Shropshire
- Sittingbourne
- Skelmersdale
- Skipton
- Slough
- Solihull
- Somerset
- South Cumbria
- South East Birmingham
- South East London
- South Glasgow
- South London
- South Manchester
- South Shields
- South West Birmingham
- South West England
- South West Scotland
- South West Wales
- Southampton
- Southend on Sea
- Southern England
- Southport
- Spalding
- St Albans
- St Helens
- Stafford
- Staffordshire
- Staines
- Stanford La Hope
- Staveley
- Stevenage
- Stirling
- Stockport
- Stockton-on-Tees
- Stoke-on-Trent
- Stourbridge
- Stratford upon Avon
- Strood
- Stroud
- Suffolk
- Sunderland
- Surrey
- Sussex
- Sutton
- Sutton Coldfield
- Swansea
- Swindon