@GrandBay wrote:@SoCalGardener then my suggestion would be to add the AU to cards where you carry the lowest balance. Lowest as percentage of available credit. Preferably cards that you charge less than 30% (some will argue 9%) of its available credit. If what you say is true about your habits and her credit profile your regular on-time payments will help the AU tremendously. This is very kind of you and I say give it a go... but first... enjoy the holiday!
Thanks! I hope you're enjoying the holiday, too! 
It's blazing hot here!
Yes, every word of what I've written is true. 
I have 100% on-time payments, 0 derogatory marks, current overall usage is about 6% (but the balances I'm carrying are on 0% accounts), scores in the 800s. I'm thinking of adding her to cards with 5-figure limits, then using them as I normally would, in other words, no huge balances, but steady charges and always...always on-time payments. Is it good or bad to PIF for these purposes? I prefer PIF (except when I charge something big and use a 0% offer, instead of digging into cash--I pay it off before the 0% ends), but don't mind carrying small balances. I just want whatever would be the most effective in terms of increasing her scores/history.
As noted, she and I have become very close; she was invaluable while I was still extremely ill, but [finally] out of the hospital. I've really come to think of her as a surrogate daughter--and vice versa. I've helped her with her credit/financial issues in other ways already, including lending her money so she wouldn't be late on a payment (on one of her itsty-bitsy limit cards), and teaching her more responsible habits. Following my advice, she was able to settle a couple of collections accounts and finally be free of them. I tried to get her on Credit Karma a while back, but she was afraid to look! 
I'm hoping to convince her to get on now so we can easily watch her progress.
@GrandBay wrote:@SoCalGardener it sounds like you should add her to ALL of your accounts!
That could be funny! My Discover card--the one I inherited from my mother--has been alive almost as long as she has!
@Anonymous wrote:
@arunkumarmm wrote:Adding her as authorized user on your card will not have any impact on your credit but the other way... all the history of your card(s) will be reflected to her history.
Whether those cards are getting used or not, does not matter. From what I know, Mostly all AU cards will have the same number as the primary card.
@SoCalGardener wrote:When my daughter was in college I added her as an AU on some of my cards without giving it a second thought. Now, I have an entirely different kind of situation, a non-relative, and would appreciate any input/advice.
Briefly, I've known her for 15 years; she's been living with me since I was discharged from the hospital after a lengthy illness, so about four years ago. She moved in to take care of me, my pets, my house. We've become very close, and we're continually mistaken for mother and daughter.
Her credit sucks!
Since she's been here she's managed to get her finances under better control, including getting approved for a couple of low-limit CreditOne and Capital One cards. When I say "low" I mean like $300! She's taken my advice to heart, and followed my idea of best practices with her cards.
I was thinking of adding her to some of my accounts to help her improve her credit. What I want to know is, can adding her to my accounts HURT my credit in any way?
The tiny bit of thinking I've done on this has been purely in my own head--I haven't even mentioned it to her yet--and involves not even giving her any actual access to the accounts. Just add her as an AU and let time go by and increase her score. Is that how it works? Or is there more to it, i.e., does she have to have a card with her name on it that gets used?
Are there any downsides you can think of? I mean other than the obvious, running up the balance on my accounts.
Although I trust her implicitly, I'm old enough and wise enough to know that *BLEEPITY-BLEEP* happens! FWIW, she knows my debit card PIN, and could easily take any/all of my credit/debit cards out of my room without my noticing. She may not be good at managing her own credit, but she is not a devious or untrustworthy person. Thoughts? Advice? Suggestions?
@arunkumarmm Not necessarily so. Because of the prevalence of people selling unused trade lines FICO introduced an anti-abuse algorithm in FICO 8. If it detects that the AU is not related to the primary account holder, or that there's no real nexus between the individuals the added account and history might be ignored.
From the FICO 8 press release:
"In addition, FICO 8 helps lenders protect against authorized-user account ‘piggybacking’ by incorporating new patent-pending technology that materially reduces the potential score impact associated with the abuse of authorized user accounts."
Oh, I didn't know this... Thanks for the info... I have added couple of friends to my accounts before who were new to the country and never had any history to help them get over the initial 6 months wait to have the score generated.. And it was reported, maybe because we have the same employer..