• 5th Night Free : For every Standard Room Reward stay of five or more nights, every 5th night is free. Members can utilize the 5th Night Free benefit on an unlimited number of stays annually. Applies only to five consecutive nights within the same full Points Standard Room Reward stay at the same property, up to 20 nights, when confirmed at time of booking. No more than four free nights will be awarded per stay. If free night is declined, reservation is cancelled, or check-out occurs before fifth night, the free night is forfeited and has no cash, Point, or Reward value. After the 5th Night Free benefit is applied, eligible members will be charged 0 points for the 5th night, 10th night, 15th night, and 20th night of the stay, as applicable. All other nights of the stay will be charged at the applicable full Standard Room Reward price. A standard room is defined by each hotel and subject to availability at participating hotels within the Hilton Portfolio. Applies to Standard Room Reward stays only, not to paid stays or Points & Money Rewards™. Does not apply when stay is booked as part of a Reward Stay offer, package, or promotion offered by Hilton or any of its partners.

The T&C are readily found for the 5th free night as above. Here is an interesting situation. I booked a Standard room award for 4 nights using points. I could not book the 5th night because that room type was not available. However, a Standard room, albeit a different type is available for the 5th night. With a phone call to the diamond desk, and presenting the case of seeing if the 5th night can be tacked onto the existing reservation and it was a 'no can do'. If the agent is trained that there is no way to accomodate this, that's not on the agent. However, it does get a little to the spirit of the 5th night. And I suppose my spirits are a bit disappointed that it just didn't work out. As a result I come to flyertalk, to see, am I just ranting or venting a little -- or is there some merit to the situation, which probably has occured to others along the way.

But, here is where perhaps I can see things getting worse. Since it seems like I have the last room of the one type. Should that room type become available for night 5, would the reservation system include your current room in the inventory, so that you really can add the one night at the end? I'm not so sure what that experience would be.