The move will give the tech specialist 21 wholly owned offices worldwide.
The bureau will be led by Erin Atan, vice-president of Asia-Pacific operations. She has been with Lewis since joining from Blackie McDonald in 2003.
Atan plans to remain based in Singapore, but will spend more time in India once the office is up and running, as of 1 August.
She will lead a team of four in Mumbai working on accounts such as RSA Security, WatchGuard and Omnitech.
London-based Lewis V-P Ilona Hitel said the agency wanted to at least double the office's size over the next year. ‘In the past six to ten months we've been getting a lot of demand for an office in India, as it is a rapidly growing market, especially in tech,' she said.
Lewis already has offices in China, Singapore and Hong Kong.
The agency, which opened a bureau in Manchester in March, also plans to open up in Düsseldorf, Germany, next month.
A survey by Lewis's London HQ of more than 100 marcoms professionals found that almost 70 per cent have assigned marketing spend to ‘social media' campaigns, such as viral marketing, for 2006. This represents an increase from around 30 per cent last year.
The results were collated at PRWeek's PR and New Media conference in London last month.