Is an authorized user harmful for automated underwriting?

[boxmover]

Title. I have an adult son flying across country for a wedding this summer and would like to send him off with a good credit card for hotel stay and potential emergency use/ Uber, etc. I've zero doubts he'd PIF any use in under 30 days for any charges to it.

He's got no credit history on any CRA. No type of loan, pfa, cc, med debt, etc. Pure cash/debit card user. Yes, I've tried and failed in the past to persuade him into at least a secured cc with his bank, to no avail.

I need to know that having an authorized user on any zero balance credit card (specifically discover or mercury visa) won't damage my mortgage credit score or credit qualifications for automated underwriting approval in the relatively near future.

The side benefit for him is he'd finally have a good start in the credit realm. I'd feel much better in general, too.

Thanks for clarification on this issue

[JoeRockhead]

You adding someone as an AU on one of your cards will have zero impact to your credit unless:  

You allow a balance to report above known thresholds that would drop your scores, and/or there's a missed payment.

[boxmover]

Thank you  

[ShanetheMortgageMan]

Your credit report won't even indicate it's an authorized user account, because you are the actual cardholder.  Your son's credit report will, however, indicate it's an authorized user account.  It'll still help his credit score, and is a great way for parents to boost their kids credit rating so they can get approved for other forms of credit on their own - which I highly recommend he gets some of his own credit as he'll need it later in life.  He may even get approved for regular credit cards instead of having to get a secured credit card.