The CD version is superior in my opinion, and the opinion of most expert users. It's cheaper for most people and more powerful. But, only you have copies of your files and you are responsible for your backups. If you want to go back to Turbotax online for 2017, there is a procedure to upload your 2016 return to online to get a head start next tax season.
More info below.
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The cheapest way to use Turbotax is to buy the CD or download for Turbotax Deluxe from a discount retailer like Staples, Costco or Amazon, and install it on your computer. If you buy the Deluxe Federal + State + Efile edition, you can prepare as many returns as you want. You can e-file up to 5 (IRS limit) and then print and mail the rest. One free state is included. State e-filing is $25 extra for each state return, but if you prefer cost over speed, you can print and mail your state return for free. The desktop version also gives you full access to all forms and worksheets, including those that are hidden in the online version.
Deluxe (on the desktop only, not online) includes all the forms needed for investments and self-employment. The Premier and Home & Business versions have more help and advice, but if you know what you are doing, you can use Deluxe at lower cost. The only potential downside is that your tax file is not stored in Turbotax's cloud. This means that it is not hackable (good) but also means that you have the only copies. If your computer crashes and you don't have a backup, your file is gone.
Turbotax online has two features that may be useful to some customers: you can work on your tax return from any internet-connected computer as well as smartphones and tablets, and your file is backed up securely online. (However, you will lose access to your old tax files unless you keep using turbotax online--think of it like a subscription.)
Turbotax online is overpriced (in my opinion) and an inferior product. There is only one seller so they control the price. I only recommend online to people who qualify to file for free.
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Turbotax Online uses a subscription model. If you use the free version, your file is locked after October 15 of the year you file. If you use a paid version, you file is locked until October 15 of the year after you file. Because you used the Desktop version this year, all your previous online files (2015 and earlier) will be locked as of October 15, 2017. You should download your tax data files and PDF copies of your tax returns before then. If you need to unlock your online account, you may be able to call customer support and provide proof of purchase of the CD version. If you use the online version next year, that will re-unlock your older online files.
Customer support can be reached via Twitter, Facebook or telephone. https://www.facebook.com/turbotax/ and https://twitter.com/TeamTurboTax.
For telephone and other support options, see the instructions below.
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