Addressing - two questions

becomingmcclain

Hello,

When addressing invitations, is it proper etiquette to use "and" or the ampersand (&)?

Mr. & Mrs. John Smith

Mr. and Mrs. John Smith

And I know that you shouldn't abbreviate E., St., Ave., etc.....but what about states? 

CA or California?

Thanks in advance for your help!

 

CMGragain

"and" is most proper.
The US Post Office prefers we use standard abbreviations, so this is fine, but may write out the state name in full if you prefer.