How should I file if I am 22, not currently a student, but totally financially independent aside from parent provided health care?

[JulieR · Accepted solution]

It depends. If you are single and not claimed as a dependent by your parents or another taxpayer, you must file a return if your gross income is at least $12,000.00. Also, you need to file if you had at least $400 in net earnings from self-employment (income minus expenses) or you had marketplace health insurance and received advanced payments for the premium tax credit.

If you are claimed as a dependent on another taxpayer's return you would need to file a return if you had: 

• Unearned income over $1,050 

• Earned income over $12,000 

• Gross income more than the larger of $1,050, or earned income up to $11,0650 plus $350 

The following TurboTax FAQ provides additional information about filing requirements. https://ttlc.intuit.com/replies/3302274

[SweetieJean]

State filing requirements may be different.

[Hal_Al]

Why are you asking the question? That is, what issue do you need to decide? "Financially independent" is not a dependent test. The related dependent tests  are:
1. The gross income test. If you have more than $4150 of taxable income**, you cannot be somebody else's dependent
2. The support test. If you provided more than half your own support, you cannot be somebody else's dependent. Support include the value of the home you live in. 

Who provides you health care/insurance is only a part of support and does not, alone, determine your dependency.

Under the new tax law, starting with tax year 2018, a working single person generally gets the same refund (or pays the same tax) whether he's a dependent or not 

**The income test is not applicable if you are a full time student, under 24,  or disabled

[SweetieJean]

I think OP is asking because parents provide health insurance.