The latest Hotel Development Monitor, from VisitLondon, reveals that there are now 71,000 branded hotel rooms in the capital.
The rise has hit the guesthouse and B&B sector, which now accounts for 28% of the market, down from 47% in 2002.
London has experienced a particular increase in design-led boutique brands such as Firmdale and Malmasion, as well as independent mid-market brands such as Apex Hotels, City Inn and Grange Hotels.
In addition, a number of consumer brand extensions such as EasyHotel and Yotel are also appearing in the capital.
Jamie Talmage, business analyst at Visit London, said the rise in branded hotels has heralded an era of improved customer service.
"The accommodation industry in London is evolving rapidly and the introduction of new brands is helping to weed out the unscrupulous operators, as is the growing popularity of online accommodation reviews," he said.
"Whilst the city still has range and character of accommodation, those that are not delivering on quality are increasingly unlikely to survive long term."
Top 10 brands by room numbers:
1. Hilton (Hilton)
2. Thistle (Thistle)
3. Premier Travel Inn (Whitbread)
4. Holiday Inn (InterContinental)
5. Various (Imperial London)
6. Marriott (Marriott)
7. Travelodge (DIC)
8. Millennium (Millennium)
9. Ibis (Accor)
10. Radisson Edwardian (Radisson Edwardian)
- Source: Visit London: London Hotel Development Monitor
- By Daniel Thomas
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