If you're seeing fewer holiday cards in your mailbox this year, you're not alone.

The tradition of sending paper greetings in a stamped envelope is being replaced by other ways of connecting in many households, often with an electronic card or a photo sent.

The experience of opening a holiday card sent to your mailbox is very different from an electronic message waiting in your inbox. But could physical cards actually make a comeback?

"This time of year there's a lot of photo cards out there," Hallmark's chief marketing officer, Lindsey Roy acknowledged in an interview with CNBC's "On the Money."

Roy said this early Christmas and Hanukkah, card sales are showing an upward trend. "It's a timeless category and one of the things we're seeing is our holiday sales are up this year."

Around 1.5 billion seasonal holiday cards were sent last year, according to the Greeting Card Association, while Americans buy 6.5 billion total greeting cards annually.

"You know the core of our business is really the individual greeting cards, the ones you pick out specifically for somebody else," Roy told CNBC. "It really is still a thriving and stable business."

According to IBISWorld, Hallmark still has a 51.2 percent share of the greeting card market. Second place is American Greetings with 23.4 percent.

Contrary to popular belief — and the growing popularity of e-cards, Roy told CNBC the perception that paper cards are vanishing is incorrect.

"A lot of people I think assume greeting cards are like books or CDs [compact disks], or some of those kinds of categories, but it's one of those categories that actually have perennial benefits over time," she said.

And she said sales are growing among millennials who are looking for something different and more lasting.