Leisure travel giants such as Expedia.com and Booking.com are eyeing up another sector of the travel market - the small business travel market, reports Skift.

These online travel booking sites and others have their sights set on a larger part of this relatively untapped market - they intend to exploit unmanaged business travel, which lacks policies that prevent company employees from using specified booking tools or sites and dictate which airlines, hotels and cars can be used.

According to estimates from David Doctorow, chief marketing officer for Expedia.com, the online market for unmanaged business travel is worth approximately $120 billion (£82 billion) globally. Winning a share of such a pot is too attractive an opportunity to miss.

While 20-30% of Expedia customers already use the site for business travel, the firm has launched a new initiative, Expedia+ Business, in a bid to capitalise on business travellers. The rewards programme offers an incentive for small businesses and their employees. Small firms can sign up to the programme free of charge, and employees are invited to join the company account and book their travel through Expedia.com.

The company then earns a $100 (£64) hotel coupon for every ten hotel nights booked, which can be used against travel costs or shared with employees toward future bookings.

As an added bonus, employees are upgraded to at least silver status in Expedia's consumer rewards program, Expedia+ Rewards, and can earn rewards in the consumer loyalty program through corporate bookings.

Just like larger firms, small businesses also get access to reporting tools which enable them to track and analyse employee travel. "Reporting really does make a financial difference to these businesses," comments Doctorow.

Expedia isn't alone in its efforts to tap into the small business market. The recently launched Booking.com For Business allows small businesses to create company accounts and lets employees book their rooms on Booking.com. Account holders also get reporting tools - although the scheme doesn't offer the same rewards system as Expedia and only applies to hotels booked through the website.

While Booking.com's scheme is global, Expedia's is targeted at US small business customers. But the takeaway is that the game is on for the small business market. Now it's up to travel firms to stay in contention by staking their claim.