Fledgling digital agency We Are Social will work on social media strategy across the EMEA region.
'We have evolved enormously as a business and there is now ample scope and budget to widen our PR remit to cover specifics,' said Alison Couper, global director of comms for Hotels.com.
All three accounts were secured following competitive pitches.
Previously, Seventy Seven PR handled consumer PR for Hotels.com, but no other UK agencies were retained. The decision to hire corporate and social media agencies, in addition to consumer help, signals a broader comms focus for the firm. Seventy Seven PR was not invited to repitch.
Couper said: 'I don't believe there's one agency that can do social media, consumer and corporate PR together effectively. I would rather have a specialist for each of them.'
Hotels.com is part of the Expedia group, which currently operates more than 70 Hotels.com sites around the world, and the UK agencies join a network of 28 retained agencies globally. The firm's European sites launched in the UK in 2001 and now attract several million unique users every month.
The UK site's key rivals include Laterooms.com and Hoteldirect.co.uk. According to the latest Hitwise UK Travel Quarterly Review, published last week, Laterooms.com is the third most popular website in the 'destinations and accommodation' category, with 3.19 per cent of visits to all such sites. Hotels.com came eighth, with 1.37 per cent of the market share. TripAdvisor topped the list with 8.22 per cent.
Couper added: 'The online hotel business is a fiercely competitive arena.'