+Most commonly counterfeited denomination $20, Most people probably think the most commonly counterfeited denomination would be the $100 bill. This was my guess when I thought about taking a stab at answering this question. However, it is not. The $20 dollar bill is the most counterfeited.
If you stop and think about it, it makes sense. Most people are watching the larger bills like a hawk, so why not use something that could fly under the radar a bit and is very common in transactions. The $20 dollar bill is perfect for this use and obviously, the criminals that engage in sort of behavior things so as well.