Board Thread:Off-Topic Discussion/@comment-5441128-20161002065443/@comment-27794543-20161002084320

If someone wants to be offended, they'll certainly find a reason to be so. But no, it's not offensive to call a man sir or a woman ma'am. However, if someone tells you they prefer not to be addressed that way, please respect their wishes.

In certain parts in the US (especially in the South), it is expected for all children to use sir and ma'am when speaking with adults. However in other parts of the US, this is practically unheard of.
 * I grew up in an area where sir and ma'am weren't used. I never heard sir or ma'am outside of films & books until I was in middle school. We had a student-teacher (university student learning to become a teacher) who would answer our teacher with "yes sir", "no sir", etc. We, the students, found it very strange because none of us had ever called a teacher sir or ma'am.
 * My first experience of being called ma'am came when I was 16/17. My boss asked me to show a new employee around. He was 5+ years older than me, but he kept addressing me as ma'am. I found it strange and amusing, but I wasn't offended. I assumed he recently moved to the state, and after a week, he realized no one used ma'am or sir around here.

The only time I've heard of a person being offended by being called ma'am, was a college girl who thought it meant being called old. Though I'm sure the internet will give plenty of other people who're offended (e.g. ) by what other's view as a sign of respect.