Lounge access if flying Lufthansa codeshare?
 

We will be flying RDU to FRA to VIE in business class on Lufthansa metal but booked via United. Will we be able to use the United lounge in RDU prior to our flight? I know we will be able to use Lufthansa lounge in FRA, but likely will get to airport a little earlier if we get access in Raleigh. Thanks.

Yes, you may use the lounge.

Yes, with the business class tickets, you will be able to access the United Club at RDU.

Do you have united/star alliance status?

Don't believe there's a RDU-FRA nonstop flight, so you're connecting somewhere in CONUSA first, the trans-atlantic business class leg is operated by LH? If LH, then no access at RDU unless you have status (you have access to UC/Polaris at the airport where the transatlantic business class LH flight departs)

returns in June 2024

On the non-stop there would be access at RDU
If connecting to elsewhere before the TATL LH , no UC access at RDU unless UC member or *G.

there is - starts in June I believe

https://www.rdu.com/lufthansa/

I connected through Frankfurt a few days ago. Was unable to use any lounge as some are closed for renovation and there was a very long line at A26. FWIW.

OP was asking about access to UC at RDU. But yes, a few of LH lounges are undergoing renovations over the next couple months, discussed in this thread: FRA lounge renovations