In the United States, your location does not play a factor.
Do & Do Not:
DO: Verbally thank your mail carrier.
DO: Gifting an item like a cup or gloves
is completely ok.
DO NOT: Giving cash or checks to your
"No one tips the mail carrier":
FALSE - This is actually very common and legal to a point,
there are federal laws on how to do this. According to The
United States Potal Service Employee
Tipping and Gift-Receiving Policy,
"All postal employees, including carriers, must comply with the Standards of
Ethical Conduct for Employees of the Executive Branch.
Under these federal regulations, carriers are permitted to accept a
gift worth $20 or less from a customer per occasion, such as
Christmas. However, cash and cash equivalents, such as checks or
gift cards that can be exchanged for cash, must never be accepted
in any amount. Furthermore, no employee may accept more than $50
worth of gifts from any one customer in any one calendar year period."