Local numbers
Virtual Landline London
Get a London 020 virtual landline from £5/month + VAT. Your number rings on your existing mobile — no app, no VoIP, no London office required.
A 020 number gives your business instant London credibility. Whether you work remotely, run a national business, or are a freelancer who wants to present a London presence, ONSIM makes it simple.
Why businesses choose a London number
A 020 number is one of the most recognised business numbers in the world. For consultants, startups, agencies and service businesses, a London number signals scale and credibility — even if your business operates fully remotely or is based outside the capital.
London-based sole traders and freelancers also use virtual landlines to keep a professional number that rings on their mobile rather than giving out a personal number to clients.
How it works with ONSIM
ONSIM routes incoming 020 calls to your mobile at network level — not through a softphone app that depends on Wi-Fi or data. That gives you reliable call quality wherever you are.
Start with Virtual Landline for a simple inbound setup from £5/mo, then upgrade to Landline SIM if you also want outbound calls to show your London number.
Who uses a London virtual landline?
A 020 number is useful for a wide range of businesses and individuals, not just those physically based in London.
Remote consultants & freelancers
Professionals who serve London clients but work flexibly use a 020 number to present a consistent London presence without paying for office space or a traditional landline.
National businesses targeting London
Companies based elsewhere in the UK use a London number to signal that they actively serve the capital's market — a particularly common approach for professional services and tech businesses.
Startups & early-stage businesses
London startups that are not yet ready to commit to a permanent office use a virtual landline to maintain a professional phone presence while the team works from wherever they are.
Understanding London 020 numbers: 0203, 0204, 0207, 0208
London has a single area code: 020. The digit that follows — 3, 4, 7 or 8 — is the first digit of the local number, not a separate code. This is a common source of confusion.
Historically, London was divided into inner (0171) and outer (0181) codes. When these were merged into 020 in 2000, the familiar 7 and 8 prefixes remained at the start of local numbers. As demand for London numbers grew, the 0203 range was introduced, and later 0204.
All sub-ranges — 0203, 0204, 0207, 0208 — are equally valid London numbers. ONSIM can provide numbers across the main London ranges, subject to current availability.
New number or port your existing one
Need a fresh London number? ONSIM can get you started in minutes. Already have a 020 landline? Number porting may be possible — contact us to check eligibility before switching.
Keeping your existing number means no disruption to stationery, your website or customer recognition.
Virtual Landline vs Landline SIM
Virtual Landline (from £5/mo): inbound calls only, rings your current mobile, simplest setup, no hardware.
Landline SIM (from £10/mo): inbound and outbound with your London number displayed, native mobile experience on a supported device.
We cover more than London
ONSIM supplies local business numbers across 650+ UK area codes. If you need a presence in multiple cities, or want to compare options nationally, we can help.