Did you enter with an actual visa?
Hello and thank you for using Just Answer.
Your question was moved to the tax section.
There are 2 ways you could be considered a resident and subject to US taxation as a resident. One is to have a green card and the other would be under substantial presence.
To meet the substantial presence test, you must have been physically present in the United States on at least 31 days during the current year, and 183 days during the 3 year period that includes the current year and the 2 years immediately before. To satisfy the 183 days requirement, count all of the days you were present in the current year, and one-third of the days you were present in the first year before the current year, and one-sixth of the days you were present in the second year before the current year. This stops people from coming and going to miss being a resident and subject to taxation as a resident..Even as a nonresident alien you may need to file a tax return. If you are a nonresident alien, you must file Form 1040NR or Form 1040NR-EZ if you are engaged in a trade or business in the United States, or have any other U.S. source income on which the tax was not fully paid by the amount withheld.
I hope this has finally put your mind at rest on how to count the time in the US.