Not always. Kiwi Flyer is correct UA and LH are particularly strict on seeing the physical card. I have tried several times at the LH lounge at Heathrow and always been asked for the physical card. On one occasion shortly after my status was renewed late last year the digital card was updated but I had not received the plastic card. I was denied access to the Senator lounge and asked to use the Business lounge as I was *only* a business class passenger