Someone I know mentioned that her daughter-in-law calls her by her first name and it makes her uncomfortable! I was just floored. I can’t imagine my child-in-law calling me Mrs. Surname. We are not formal people in any way. Perhaps I’m in the minority?
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Was she expecting to be Mrs X or some variant of Mom?
Not an in law yet. DH and I called each other’s parents by first names. Some viewed that as less than “Mom” back in the day.
I call my in-laws by their first names.
Mr R calls my parents mom and dad.
My mom calls my dad’s parents dad and (grandma’s name)- she’s a step parent so she’s always gone by first name. Dad called mom’s parents by their first names.
It would be bizarre to me to ever call an in-law Mr/Mrs/Ms X. But then again, I come from a family that hates being called Mr/Mrs/Ms X.
Our son-in-law calls us by our first name. We told him to do so. On the other hand, our daughter’s mother-in-law requested to be called “Ma” which made our daughter uncomfortable.
Our youngest daughter is currently in a serious relationship. His parents told her to call them by their first names and we’ve told the young man the same.
Our SIL calls us by first name, and D does the same with her in-laws.
SIL calls us by our first names (which is what we prefer). H and I have always called each others parents by their first names, too.
A member of our extended family still calls her MIL “Mrs. last name” after more than 30 years of marriage. That seems odd to me.
My inlaws wanted me to call them “mom” and “dad”. The problem was they never responded to those names when I used them- probably because they only had sons and weren’t used to being addressed in that manner by a female! I soon started addressing them by their first names and they never complained- and they also responded when I addressed them 
SIL 2 called us Mr and Mrs Hoosiermom when he first started dating D2 when they were both in highschool. Somewhere along the way (still years before they married), probably when he graduated from college, we told him it was fine to call us by our first names. Since we frequently see D2 and her husband in social settings with his parents, there is never a problem with him having 2 different persons to address as “mom” or “dad”. D1’s husband was in his late 20’s when he started dating D1; the first time we met him we asked him to call us by our first names which he continues to do.
DIL calls us by our first names. That’s fine with me. My in-laws would never have been OK being called by their first names. Until we had kids and I could call them Grandma and Grandpa, I never referred to them by name nor “mom” and “dad”.
Both my DIL and SIL call us the same as what my children call us. They worked it among themselves without any input from us.
Both H and I call each other’s parents by first names and did ever since we started getting serious dating. I would likely prefer my kids’ eventual partners to call us by our first names.
Both my kids are engaged. Their partners call me by my first name. I’m 100% fine with that.
I called my in-laws “mom” and “dad” when I married. My husband did the same with my parents.
My D’s husband calls me and my hubby by our first names, and D does the same re his parents. They were in their 30’s when they met and married, and we all used first names from the start. (Now we have added Grandpa and Grandma to the mix. )
Son and his fiancee are younger, mid-20s, and both use “Mr. and Mrs.” to address the others’ parents. We sign cards, etc. to future DIL with our first names, and I have said that first name would be fine by me. But this couple met early in high school, and the habit is entrenched.
I am fine with either, but would prefer first names all around.
I think I avoided calling my in-laws anything. I was probably asked to call them by first names, but I’m not sure. My mother called her in-laws Mother B and Father B, which was better than Mr and Mrs and I don’t think first names would cut it in her generation. I’m not sure what my son’s girlfriend calls us, but I do know most of his friends call us by our first name, so I imagine she does too when she needs to.
My sons-in-law and my other two Ds’ significant others all call us by our first names. We have done this since the first serious relationships for our 5 Ds. I cannot imagine expecting any SIL or DIL to call me Mom or anything equivalent. I feel the same about being called Mrs. It’s just silly, in my opinion.
My in-laws never suggested that I call them by their first names, and, thus, I never called them anything. It was ridiculous. My H has always called my parents by their first names and they have a wonderful relationship. I don’t get why so many people are uncomfortable with being called by name.
At the beginning of my marriage, my husband asked my MIL what she wanted to be called. Some people called her by her nickname, and her other 2 DILs called her by her full name. The answer came back: she wanted to be called Mrs. G! For years I didn’t call her anything, and then I used her full name, same as my SILs. I had never heard of calling an in-law by their last name and the idea made me feel like an outsider.
First names for my kids SOs, I make sure to introduce myself that way and ask them to call me that if they go down the Ms. or Mrs. path. Saves switching over later on. I called my FIL & MIL by first names, and my ex-H did the same with my parents. OP, I think you are more formal than a lot of posters out here…
My parents always called both sets of grandparents mom and dad. They called all my great grandparents,
grandma & grandpa. DH & I used to call our MIL/FIL’s by their first name. When we started having kids we changed it to grandma/grandpa first name.
My sons GF calls DH & I, mom & dad.
I think the important thing is that you call the person something they are ok with.
My husband and I call each others parents mom and dad now, but when we were first married, I didn’t call my MIL anything! I use to wait until she was looking my way and then would address her. My FIL had a nickname that everyone called him, so he was easy.
My DIL of only 4 months has called us by our first name, but I think she is not totally comfortable with that. We told both kid’s SO that they should call us by our first names, and once married, if and only if they were comfortable, mom and dad. I think my SIL to be will take a good while, if ever, to address us as mom and dad as he is more reserved. I don’t know if my DIL will every call us mom and dad, but that is ok with me. My son doesn’t call her parents anything, but will call her mother by her first name soon. The dad is a bit intimidating and my son is just not comfortable calling him by his first name just yet.
Some spouses do not like calling their in-laws mom and dad as they feel that they only have one mom and dad and that is their birth parents.
Actually, once we had kids, it was easy to refer to my in laws as grandma and grandpa, since that is what the kids called them. Unless I called them on the phone, it wasn’t really an issue.
Both my husband and I call our in laws mom and dad. I asked daughter’s fiancé to call us mom and dad, or our first names if he was more comfortable with that. He chooses to call us by our first names, and I’m okay with that.
My first DIL calls us by our first names now but it was hard because she knew us from when she was in middle school and dated our son from 15 so called us Mr. and Mrs. back then. Hard to change after more than 10 years. Second DIL had no problem calling us by first names because she met us when she was in her late 20’s.
My husband calls my parents by their first names. I never called his parents anything until they became grandparents. I never felt comfortable with them.
Can’t imagine calling in laws Mr and Mrs.