Filing as a dual status residents

1) For the 1040, you cannot use the standard deduction.  You  can itemize certain allowable deductions.  You cannot claim a personal exemption deduction.

See How do I change from the standard deduction to itemized (or vice-versa)? and select Itemized deduction even if you do not have any to enter)

 

2) You can use the 1040-NR as the statement, just write  "Dual-Status Statement" across the top.

 

3) The first-year statement is separate and must include your name and address and specify the following:

• That you are making the first-year choice for the current tax year 
• That you were not a U.S. resident in the prior tax year 
• That you qualified as a U.S. resident under the substantial presence test in the following year
• The number of days of presence in the U.S. during the current tax year (2020) 
• The date or dates of your 31-day period of presence and the period of continuous presence in the U.S. during the current tax year 
• The date or dates of absence from the U.S. during the current tax year, if any, that you are treating as days of presence under the first-year choice

 

 

But what about tax brackets.

Let's say If I earned 100,000$ in 2020 of which 50,000$ was earned as non-resident and 50,000$ as a resident.

In this case,

Does the brackets are applied individually on each income portion?

The current tax brackets are

• 22% for incomes over $40,125 ($80,250 for married couples filing jointly);
• 12% for incomes over $9,875 ($19,750 for married couples filing jointly).

So does that mean I pay
Non - resident tax = 0.1 * (9875) + 0.12 * (40125 - 9875) + 0.22* (50000-40125) =6790
Resident income = 0.1 * (9875) + 0.12 * (40125 - 9875) + 0.22* (50000-40125) = 6790

It depends. 

You are a dual-status alien when you have been both a U.S. resident alien and a nonresident alien in the same tax year. Dual status does not refer to your citizenship, only to your resident status for tax purposes in the United States. In determining your U.S. income tax liability for a dual-status tax year, different rules apply for the part of the year you are a resident of the United States and the part of the year you are a nonresident. The most common dual-status tax years are the years of arrival and departure.

 

if your income was foreign earned income or passive income earned from investments, you could exclude that portion of the income.  Your calculations otherwise look correct.

Here is an IRS link to instructions about the taxation of Dual-Status Aliens.