The most common and respectful way to say it is simply:

“Happy Veterans Day, and thank you for your service.”

If you want alternatives that many veterans and etiquette guides recommend, you can say:

  • “Thank you for your service and sacrifice.”
  • “Honoring your service today and always.”
  • “Grateful for your service this Veterans Day.”

When speaking directly to a veteran, many people prefer leading with thanks rather than only “Happy Veterans Day,” since the day is about honor and remembrance, not just celebration.