The Friday File: The average dollar bill lasts 5.8 years. The average $5 bill, 5.5 years, while the $10 bill lasts just 4.5 years, less than any other note. $20s average 7.9 years, $50 bills last a slightly longer 8.5 years. The longest lifespan, the C-note at 15 years. The Bureau of Printing and engraving produces 7.8 billion banknotes a year at a cost of $700 million; almost ten cents/banknote.