Even if you owe, you should file an income tax return to avoid late filing penalties.
For 2018, you may be able to use TurboTax Free File Program. It's geared towards lower-income filers, regardless of tax return complexity, and is only offered through the IRS Free File Alliance (FFA) program. No upgrades are available.
To file 2017 income taxes, see Can I still use TurboTax to file a 2017 return?
