- A X M
- A X A Art Insurance
- R X Barnes & Co
- W X Electronics
- C & X Fashions Ltd
- F X Import Ltd
- C X M Interiors
- E X Logistics
- P X London Ltd
- E X O Ltd
- T X Media & Event Consultancy
- B X Motors
- F X Music
- M X Plant Sales Ltd
- I X O Publishing
- F X Rentals
- 2 X B Systems
- F X Travel
- 1 X-Treme Clean
- X X X-Vision
- X10 Computers
- X9
- XA Services
- Xanadu Productions Ltd
- Xara Computers
- Xargo
- Xaverian Missioneries
- Xavia Fashions Ltd
- D Xavier
- Xavier Auto Clinic
- A Xavier & Co
- Xavier Young
- Xbridge Ltd
- Xccessories MC Ltd
- XChange International
- Xchanging
- Xclusive Bodyworks
- Xd Software
- Xeba Design
- Xelas Ltd
- Xen
- Xenith Document Systems
- Xenith Group
- Xenomorph Software Ltd
- Xenon Services
- Xenos
- Xenxpress
- Xequine Leathergoods
- Xero Graphics
- Xeta
- Xian Bar And Chinese Restaurants
- Xian Chinese Restaurant
- Xibit Accessories
- Xiexie Green Tea
- Xile Leathers Ltd
- Xinit Systems Ltd
- Xiona
- Xiong Mao
- Xios Transcast Corporation
- Xium Interiors
- Xj Consulting
- XL Callshome.Com
- XL Environmental Ltd
- XL Marketing & Office Supplies Ltd
- XL Recordings
- XL Winterthur International Insurance Co Ltd
- XLFX
- Xoomworks
- XOR Ltd
- Xotica
- Xotica Spa Touch Clinic
- Xotik Plant Shop
- Xou Solutions Ltd
- Xpedite Systems Ltd
- Xperience (PEG Associates Ltd)
- Xpertise Training
- Xpertz
- Xpreme
- Xpresion
- Xpress Cars
- Xpress Signs Ltd
- Xpression Post Production Services Ltd
- Xpressions
- Xrefer Ltd
- Xrisafi Jewellers
- XS Tronix
- Xstrata Services (UK) Ltd
- Xtal Security Systems Ltd
- Xtempus Ltd
- Xtra It Resources
- Xtra Save Supermarket
- xtra Special Sports Ltd
- Xtracks
- Xtraprint
- Xtravaganza Recordings Ltd
- Xtreme
- Xtreme Care Ltd
- Xtreme Information
- Xtreme News
- Xube Ltd
- XYZ