Moneydance 2015 is a free upgrade to anyone who purchased a license key for Moneydance 2014. This is true if you purchased an upgrade key or a new key. You can upgrade at no cost by using your current Moneydance license key.
If you purchased Moneydance through the Mac App Store or through Amazon.com, please download Moneydance 2015 there.
If you purchased Moneydance 2012 or earlier you are entitled to a discounted upgrade price of $24.99. If you want to run Moneydance 2015 you will need to purchase an upgrade key. To determine whether you are entitled to a free upgrade or to confirm your license for a discounted upgrade use our convenient key tester here.
If you don't know your license key you can see it by running Moneydance and selecting Help->About Moneydance (or Moneydance->About Moneydance on a mac), or by using the "Lost Key" tool on the purchase page.