Five years in business, and that's a moment. Not every organisation celebrates this in a big way, but it doesn't have to. Being original isn't about scale, but about the choice. Popular formats for a 5-year anniversary:
Pop-up experience: surprise staff at an unexpected moment with a surprise event. No one knows what's coming. That makes it unforgettable. Team trip: go away for a day or weekend with the team. A shared experience outside work strengthens the bond more than a formal party. Community moment: involve clients or partners in the anniversary, let them say what you mean to them. That creates an authentic story.
Whatever you choose: make sure there's recognition for the people who've been there for 5 years already. That recognition is the core of every anniversary celebration.