In a large mixing bowl, combine the kidney beans, chickpeas, and green beans.

Add the diced red bell pepper, chopped red onion, and diced celery to the bowl.

In a separate bowl, whisk together the olive oil, apple cider vinegar, Dijon mustard, honey, salt, and black pepper.

Pour the dressing over the bean and vegetable mixture and toss to combine. Serve chilled or at room temperature.