Don't leave your sender guessing. Let them know when you'll be out and the date you'll be back in the office — not when you're returning home.
It’s very likely that you’ll set up an auto-reply message while you’re at a conference or any other business event. What’s more, some of your prospects will be there as well, so you should use an opportunity like that to meet them in person and strengthen that relationship.

Our office will remain closed for Christmas. We assure you that all your emails will be answered as soon as we return to the office.
But your out-of-office message is as much for you as it is for the people receiving it, especially during the pandemic. “Boundaries have taken a big hit right now,” Ritter says. There’s a lot of pressure associated with missing something at work, and that stress has been heightened without the typical separation between office and home and with the added fear caused by an uncertain economy. An OOO message is a chance to set expectations, “to give yourself some breathing room and to ensure other people aren’t thinking negatively about you,” Ritter says, and it’s crucial for your mental health.