Well... I wouldn't tell you not to try this, but I have one story to illustrate why it might not always work.

Several years ago while traveling to San Antonio on business I checked in for three nights at the Rivercenter Marriott. The front desk associated did their thing and handed me my key with no fuss whatsoever. I was quite impressed to ride the elevator to the top floor and to find myself in the Presidential Suite, grand piano and all! In a classic case of Murphy's Law at work, of course I was traveling on my own and didn't even have any coworkers to impress or help me enjoy the enormous suite. It turns out I had to extend two more nights, which the front desk was happy to do, but they were quite clear that I had to change rooms. The PS was booked by a paying guest starting on my checkout date, so I had to downgrade to a standard concierge room. I wasn't the least bit put out (obviously!), but I don't think I'd use the "book one night hoping for an upgrade then ask to extend counting on staying in the same room" strategy in the future...

Platinum Upgrade
 

It doesn't hurt to ask. I am genuinely friendly with the check in staff, and a few weeks ago was extremely successful. I was given an upgrade from a 1 bedroom suite to a 2 bedroom suite at a Residence Inn. I thought there was little possiblity of being upgraded as the booking was for 8 nights. However, the check-in staff member was extremely helpful and more than happy to grant my request.

Glad it worked for you. ^

Last time I was at the Rivercenter property, I had two rooms reserved. One of them was a standard suite and the other was a standard room with a balcony twice the size of the room overlooking the Riverwalk. Both rooms were on the 33rd floor and were down a short hall from one other. Simply amazing service from a nice property.

I know everyone probably knows, but just as a reminder, suite upgrades are not a part of the MR program. So if you get one, consider yourself lucky.

I think we've all noted that from the beginning. Suite upgrades are up to the individual property and, depending on where and how long you stay, you may find a pretty good upgrade rate if you ask nicely.

I've never asked for an upgrade and generally felt that the extra space is wasted while on biz travel. I've received one upgrade without prompting (Ft. Worth CY Fossil Creek). It was nice but nothing worthy of the extra effort to receive.

In general, I feel one would not even be offerred even if I asked. I always stay on a gov't rate which is usually well below the rack rate. Tonight I'm staying at the RC Boston Common ($206/night). Current available rack rate is $575. What do you think are my chances for scoring an upgrade. Anyone? Anyone? Bueller?

I'll just sit back, relax and enjoy the base RC room, which is likely going to be lots better than an upgraded room at nearby CY (also at $206 an the only other available gov't rate Marriott property for the night).

First I would like to thank all of you for your great information. I, like the originator of this post, am a platinum member that rarely asks for an upgrade. Basically, I just like a clean room to sleep in while out for work.

I am using my annual free night certificate (from my Marriott card) to take my wife to the Battlehouse in Mobile, AL. I want to actually get whatever I can out of my platinum status for the night so I read all of your information and called the hotel. It was a very pleasant experience and I have been upgraded to a "honeymoon" style suite for the night (which I haven't told my wife about.)

My advise for anyone in a situation like mine is to just call the hotel and explain what you need. Hopefully it will work out for you too.;)