I don't know that polymer bills last any longer. Canada's old dollar bills used to last ~1 year [1], and polymer bills are said to last two to three times long

I don't know that polymer bills last any longer. Canada's old dollar bills used to last ~1 year [1], and polymer bills are said to last two to three times longer [2]. (I can't find a more precise estimate.) But US dollar bills are made of linen and last much longer, 56 months [3]. The high durability of US "paper" money is another reason that switching low denominations to coins makes no sense in the US. [1] http://www.npr.org/news/graphics/2012/04/pm-loonie-report.pdf http://www.npr.org/news/graphics/2012/04/pm-loonie-report.pd... (page 6) [2] http://www.zdnet.com/blog/government/polymer-to-replace-cotton-in-canadian-currency-notes/7537 http://www.zdnet.com/blog/government/polymer-to-replace-cott... [3] http://www.gao.gov/products/GAO-12-307 http://www.gao.gov/products/GAO-12-307