Hilton HHonors members who have an American Express Corporate Card will get Silver elite status when registering (or enrolling) and completing two stays in the next 90 days and Gold status if you complete four stays within the same timeframe. Silver offers 15 percent bonus on all HHonors base points earned, complimentary access to hotel health clubs and access to elite only awards. Gold status offers complimentary WiFi at select properties, space-available room upgrades and continental breakfast at select brands and a 25 percent bonus on base points. Visit http://insideflyerus.wpengine.com/link/?11793 to learn more.

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Note that this is for corporate AMEX Hilton cards only and although the offer is still valid at this writing, according to the fine print, “Offer may be terminated without notice.”