Although Palo is dressier than the regular dining rooms on casual nights, Palo is not "all formal all the time" by any stretch of the imagination.
Here's what the official DCL website says about dress for Palo in the Onboard Dining FAQ.
Dress for dinner at Palo on all cruises:
Men: dress shirt or jacket
Women: dress or pantsuit
On formal night (and to a lesser extent on semi-formal night) on the Disney Magic, you will see some tuxedos in Palo. On other nights on the Magic or any night on the Wonder, a tuxedo in Palo would be rare.
On the other hand, if you want to wear a tuxedo to Palo, go for it! It's fancy, dressy place. Live! Dress fancy! Make it a special evening!
My DH will have a tuxedo on at Palo. We are renting one for the cruise and he is planning on wearing it on Formal night and semi formal. We have ressies at Palo on semi formal night. I can't wait!!!!
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