It's worth it to actually know how to do taxes for real. On paper, following the instructions yourself.
This is a great time to learn, because you get to learn the new version of the forms.
You can hit the library and get copies of the popular paper forms, or you can get PDF versions of the forms and instructions. Get real Adobe Acrobat Reader, because you can actually type the numbers/values into the PDF versions. I put in everything except my SSN, save it, print it, handwrite the SSN and signature, and stick it in an envelope with a stamp and mail it to the IRS. Now I have a local copy to archive on my PC.
I have to stand behind that 1040. I'd like to be able to acutally see it in the future, not have it be bits and blits in somebody else's cloud, or in some weird file format only one app can read. (Nor do I want my SSN in those places, which could be hacked). PDF is common and reliable. (And again, no SSN there either).
One more thing, IRS can reject online "filings". In effect they strongarm you to accept numbers you disagree with, otherwise you've failed to file. When you file paper, IRS must accept that you filed on time, then you squabble with their Andover office about the details.
Consider these points:
Safe keeping. If you ever lose the physical copy of your W2, or it somehow gets destroyed and becomes unreadable, you'll have a local back-up file with this years extension (ex .tax2018) that would allow you to reload your entire return with that years version of TurboTax. This is much easier than having to contact and pay the IRS for a copy, which literally takes weeks for them to process.
Security. As the other user pointed out, downloading and installing TurboTax locally at least prevents you from inputting all of your private financial information directly over the web.
Take your time. If you're missing a specific piece of information or document that's required in order for you to complete your return, or maybe something just comes up and you have to step away, your online session will eventually timeout and you'll need to pick back up from that page. This isn't a problem if you're working locally on your own machine.
From the TurboTax site -
You can file with TurboTax Free Edition if you use form 1040 with no attached schedules.
Simple tax situations covered in TurboTax Free Edition:
- W-2 income
- Limited interest and dividend income reported on a 1099-INT or 1099-DIV
- Claiming the standard deduction
- Earned Income Tax Credit (EIC)
- Child tax credits
Situations not covered in TurboTax Free Edition include:
- Itemized deductions
- Business or 1099-MISC income
- Stock sales
- Rental property income
- Credits, deductions and income reported on schedules 1-6, such as the Student Loan Interest Deduction
If your entire return is only to reflect the W2, I’d suggest taking advantage of the free filing. I’ve had stock sales and rental property since I started filing, so I’ve never had the free option as a choice.