London's black cabs are an icon and a genuinely excellent service — Knowledge-trained drivers who know every street, no pre-booking needed, and a legal right to carry you anywhere in London. So why do millions of people choose private car services instead? This is an honest comparison from someone who operates a private car service in London — including the cases where a black cab is the better choice.
Black cabs have The Knowledge — London's most rigorous taxi driver training programme, requiring 2–4 years to complete and testing drivers on thousands of London streets and landmarks. A black cab driver is unlikely to need sat-nav to find any address in London. They can be hailed on the street or found at taxi ranks, so they require no pre-booking. They are metered, so shorter journeys sometimes cost less than a pre-booked private transfer. They are TfL-licensed and regulated to the same standard as any private car service.
The meter is both the strength and the weakness. In heavy traffic — which is most of London, most of the time — the meter continues running regardless of progress. A Heathrow to Mayfair journey in rush-hour traffic can reach £90–£110 on the meter. There is no pre-booking guarantee, so at peak times (Friday and Sunday evenings, bad weather, after major events) the queue at Heathrow's taxi rank can be 30–45 minutes. There is no meet and greet in the arrivals hall — you must walk to the taxi rank, often with all your luggage, after already clearing customs and collecting bags.
A pre-booked private car gives you a fixed price agreed before travel — £60 from Heathrow to Mayfair regardless of traffic, time of day, or how long the journey takes. Your driver is in the arrivals hall when you exit customs — not in a queue outside. Flight monitoring means delays and early arrivals are handled automatically. For groups of 2 or more, the fixed per-car price is almost always cheaper than a metered cab covering the same journey.
| Black Cab | Private Car (LATD) | |
|---|---|---|
| Heathrow to Mayfair | £65–£100 metered | £60 fixed |
| Pre-booking possible | No | ✓ Yes |
| Meet in arrivals hall | No | ✓ Yes |
| Flight tracking | No | ✓ Yes |
| Surge/variable pricing | Yes (meter) | No — fixed |
| Electric vehicle | Some | ✓ 100% |
For a quick in-city journey where you want flexibility and don't mind the meter — a black cab is an excellent choice. For airport transfers, pre-planned hotel journeys, groups of two or more, families with luggage, or any journey where price certainty matters — a pre-booked private car is consistently better value and more convenient.