How to say hotel room numbers?

This is a very minor question that bothers me more than it should. When I return to a hotel and ask for my keys how should I say the room number. For example, say I am in room 316 is it more normal to say sanbyaku juu roku or san ichi roku? I know that both are understood and at home I would use the latter.

Yes, both are understood, but just out of gut feeling, I know I would say san-ichi-roku.

Personally (I’m a Japanese) and unconsciously, I often use the former, sanbyaku juu roku, but I also happen to use the latter when I want to make it clear.
When it comes to numbers with four figures, I think I have tendency to use the latter, 2316, ni san ichi roku, for example. That's nothing but my personal habit, but I'm sure that the latter is always clear even if it lacks a certain natural tone.
Therefore, we almost always say telephone numbers in the way of the latter.

Thanks to both of you. It probably says a lot about me that I worry so much about something so trivial.

Don't think so serious.

If front staff no changed he/she remembering you(name/face) very usual
so just say "I'm home!(ただいま!)" and "Key pls!(鍵、お願いします)" :)

If staff changed just say your room number in EN
no need remembering/studying JP raeading od counting for only in this case.

Just would like to try/say in JP (as standard)
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316号室のstanです。(部屋の)鍵をお願いします。
Sanbyaku-juu-roku goushitsu-no Stan-desu. (Heya-no)Kagi-wo onegai-shimasu.
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Copy to above JP text box then click "speaker" button.
http://voicetext.jp/
If you are a man, switch to male character icon better.
通常版 is normal size as sound file.
Mictro版 is light size than normal.

No problem "san-ichi-roku" reading instead. (mentinoned by AK)
If "306" will be "san-maru-roku" usual. (using "zero" possible)
"maru(まる/マル/円/丸)" means just "circle".
Japan natitonal flag called "Hi-no maru(日の丸)".
https://en.wikipedia.org/wiki/Flag_of_Japan