Since Intuit has discontinued this version, your best options are secondary markets where individual sellers list older software. eBay
Buying software that is over 10 years old comes with several technical and legal hurdles: Can I still file my 2013 taxes - TurboTax Support - Intuit buy turbotax 2013 online
: This is currently the most reliable source for older software years. You can find various versions like or TurboTax 2013 Home & Business Go to product viewer dialog for this item. for around $37.00. Since Intuit has discontinued this version, your best
: While Amazon is an authorized retailer for current versions, 2013 inventory is often limited to third-party sellers. Ensure the seller has a high rating and confirms the inclusion of a valid license key. for around $37
: Some retailers like OldSoftware.com specialize in legacy software and occasionally carry factory-sealed versions. Important Considerations Before Purchasing