I call my mom “mom” unless I’m joking around and call her “mommy” or “Jan.”
I call my dad and stepmom Dad and Dianne to their face. Behind their backs I call them Charles and Camilla.
28, female, Minnesota.
Mom and Dad. Step-parents go by their first names.
When my kid was little(r) he would sometimes call me “Lady,” and would more-often-than-not call his dad “Honey.” Also by our first names, occasionally. When he was trying to get my husband’s attention (not always an easy task) it would sound like this: “Daddy?..Dad?..Lee?!..Honey!!!” This from a three-and-a-half year old. 
Now he sometimes calls my by my middle name when he’s being silly.
But mostly he calls us Mom and Dad.
I had some neighbors, born and raised in the area, who are called Mother and Father by their kids (ages two and four).
Sorry for the rambly tangent.
Female
33
Raised in Alaska by midwestern parents.
Currently living in the midwest.
Tried to get my kids to call me “Big Daddy-o” or “Cool Cat Dad”, but neither took.
These days they often refer to me as “the Jerk”, which causes me to observe that they are “the Jerk’s kids.” Can ya feel the love?!
Maman and Papa growing up
Maman and “Chef” (long story) now
Female, 28, Francophone, Canada