41 CFR § 301-73.301
How do we obtain travel payment system services?
June 9, 2020
You may participate in GSA's or another Federal agency's travel payment system services program or you may contract directly with a travel payment system service if your agency has contracting authority and you are not a mandatory user of GSA's charge card program.
Note to §301-73.301: Under the new GSA charge card program effective November 30, 1998, it will be your responsibility to select the vendor that will be most beneficial to your agency's travel and transportation needs.