Some of the largest online leisure travel sites, including Expedia.com and Booking.com, want a bigger slice of the small business market.

The piece of the market they are looking to make strides in is the unmanaged business travel sector. That means companies and their employees where there are no stringent policies on which booking tools or sites to use and which airlines, hotels and cars are acceptable or not.

David Doctorow, Expedia.com’s chief marketing officer, estimates that the online market for unmanaged business travel is about $36 billion in gross bookings in the U.S. and some $120 billion globally.

Doctorow says 20 to 30 percent of Expedia customers already use the site for business travel. Seeking to capitalize on that trend, Expedia launched Expedia+ Business, a rewards program for small businesses and their employees.

Small businesses can sign up for free and invite their employees to join the company account and book on Expedia.com. For every 10 hotel nights booked, the company then earns a $100 hotel coupon, which it can use to defray its travel costs or share with employees toward future bookings.

With enrollment, employees get upgraded to at least silver status in the Expedia consumer rewards program, Expedia+ Rewards, and their corporate bookings count toward rewards in the consumer loyalty program.

As with larger corporations with managed travel programs that sign up with Expedia’s Egencia corporate travel unit, the small businesses in the new Expedia program get reporting tools enabling them to track and analyze employee travel.

“You can’t measure what you can’t see,” Doctorow says. “Reporting really does make a financial difference to these businesses.

Expedia’s announcement about its new small business program follows Booking.com’s recent launch of Booking.com For Business, which enables small businesses to create company accounts and to have employees book their rooms on Booking.com. As with Expedia+ Business, Booking.com For Business accounts get reporting tools.

Expedia+ Rewards focuses on hotels for rewards accruals but enables company employees to book flights and cars, as well. Booking.com For Business doesn’t have a loyalty program associated with it and is hotel-only.

Expedia’s new business travel program for small businesses is U.S. only while Bookng.com’s is global.

Photo Credit: Business traveler at Chicago O'Hare Airport. Jason Mrachina / Flickr