If a lower fare is found on another online source, submit the itinerary to CBT via your travel agent team or the online helpdesk within one (1) hour of the original booking. The lower rate must be available for booking on Concur or other US-based website at the time you contact CBT. The price guarantee is available only for exact itinerary matches -- same air carrier, class of service, identical fare rules and restrictions (including applicable refund, change and cancellation policies), the exact same dates, flight numbers and times of travel for all legs of the trip. Click here for more details.
CBT offers Fare Checker module
Christopherson Business Travel offers a Fare Checker module which automatically searches every reservation for savings of at least $50 within 24 hours of booking and savings of $300 or higher after the 24 hour void window for domestic tickets and $500 or higher for international tickets.