Navigating Dual-Status US Tax Returns: What Non-Citizen Part-Year US Residents Need to Know for 2026

Written by Hannah Jeffs

For many individuals, tax returns can be complex, particularly where residency status changes during the tax year. If you move to or from the US partway through a tax year, you may find that dual-status tax rules apply.

Whether you are exploring the impact of dual-status taxation, managing an alien dual-status position, or preparing your US tax filing, we have set out the key aspects to consider for the 2026 tax season.

What is a dual-status?

A dual-status taxpayer is someone who is treated as both a US tax resident for part of a tax year, and a non-resident for the remaining portion of the same tax year.

To put this simply, if your residency status changes during the year, you may be classified as dual-status.

Dual-status applies in the following scenarios:

• You move to the US and become a tax resident partway through the tax year
• You leave the US and lose your tax residency status
• Your immigration status changes (for example, you obtain a green card)
• You meet the substantial presence test mid-year (outlined below)

Alien Dual-Status

The term alien dual-status applies specifically to non-US citizens. An alien dual-status taxpayer is someone who is a resident alien for part of the year, and a non-resident alien for the rest of the tax year. This classification is determined by IRS residency rules, not by citizenship or passport status.

Dual alien status is determined by the following two tests:

• Green Card Test

You are a US tax resident if you hold a green card at any time during the year

• Substantial Presence Test

You are considered a resident if you are in the US for:

• • At least 31 days in the current tax year, and
  • 183 days over a three year period (weighted formula)

Meeting either of these tests during the tax year can result in dual alien status.

How does dual-status work in practice?

A key part of understanding dual-status is knowing how your income is taxed.

For tax purposes, the tax year is split into two distinct periods:

• Resident Alien Period

During your resident alien period, you are taxed on worldwide income. This will include foreign employment income, investment income and gains as well as overseas rental income. All global income must be reported for the portion of the year that you are a US resident.

• Non-resident Alien Period

During the period you are considered non-resident alien, you are only taxed on income sourced in the US. This includes US earnings, business income connected to a US company and certain US investments. Foreign income earned during this period is generally excluded from US taxation (unless certain exceptions apply).

When filing a dual-status tax return, attention to timing is essential. Income must be allocated to the correct residency period to ensure this complies with the IRS rules.

Filing for the wrong period could lead to penalties or unnecessary tax payments. A dual-status tax return requires careful handling because you are effectively filing under two sets of rules.

How to file a dual-status tax return?

The form that you are required to file depends on your residency at the end of the tax year.

If you are a US resident alien at the end of the tax year, then the following forms are required:

• File Form 1040
• Attach Form 1040-NR as a statement

If you are a non-resident alien at the end of the tax year, then the following forms are required:

• File Form 1040-NR
• Attach Form 1040 as a statement

When preparing a dual status tax return, remember to label this clearly as “Dual-Status Return” with resident and non-resident income reported separately.

A lot of standard tax software does not support dual-status filing, meaning the filing often requires manual preparation or assistance from a tax professional.

Key Limitations of Dual-Status

While understanding what dual-status means is important, it is equally important to understand its limitations.

Some of the limitations are as follows:

• Dual-status taxpayers are generally not eligible to claim the standard deduction and must itemise their deductions instead
• You typically cannot file a joint return. However, in certain cases, such as being married to a US citizen, you may be able to elect to file jointly
• Many common credits are restricted or unavailable. Please note, dual-status taxpayers generally cannot claim the following:
• Earned income tax credit
• Education credits
• Certain dependent related credits
• Dual-status taxpayers are not eligible to use the Head of Household filing status, even if they meet the criteria

These limitations could significantly impact your final tax bill.

If you meet the relevant criteria, you may be able to elect for to be treated as a full year US tax resident instead of filing a dual-status return. This election can allow you to retain access to the standard deduction and, where applicable, file jointly with your spouse. This approach may also increase your eligibility for certain tax credits.

However, with this approach, you are still required to report worldwide income for the entire tax year which may increase your taxable income. Therefore, the following needs consideration when electing to file as a full year resident:

• Your total income
• Foreign vs US income
• Marital status
• Eligibility for credits and deductions

Often, reviewing both options helps identify the most tax efficient choice.

Tax Treaties

Tax treaties play an important role for alien dual-status taxpayers and can help reduce the risk of double taxation. Treaties will provide residency tie breaker rules and clarify which country has the primary taxing rights.

When you are considered a resident in two countries, the treaty will typically assess certain factors such as your permanent home, economic ties, and immigration status to determine your tax position.

To claim treaty benefits, you must file Form 8833, clearly disclosing your position in accordance with IRS rules.

Common Mistakes to Avoid

Some of the frequent pitfalls that are made when filing under dual-status are:

• Misallocating income between periods.
• Claiming the standard deduction incorrectly.
• Using unsupported tax software.
• Ignoring the full year election option.

To minimise errors, carefully track your entry and exit dates and maintain detailed income records by residency period. If in doubt, always seek professional guidance if required.

2026 Filing Season (2025 Tax Year) Deadlines

It is worth noting the filing deadlines for 2026. For income received in the 2025 tax year, the 2026 filing dates are as follows:

15 April 2026	Standard deadline
15 June 20ual 26	Automatic extension for individuals living abroad on the filing deadline
15 October 2026	Extension deadline (if requested)

 

Example of a Dual-Status Scenario

Below we have demonstrated how a dual-status tax scenario works in practice.

An individual moves to the US on 1^st July. In doing so, they then meet the substantial presence test later that year. This is broken down as follows:

• January – June = Non-resident Alien period
  • Taxed only on US sourced income
• July – December = Resident Alien period
  • Taxed on worldwide income

As they are a US resident at the end of the tax year, they are required to file a Form 1040 and attach a Form 1d040-NR.

Summary

In summary, moving to or from the US can affect your tax status, so it is important to understand whether dual-status rules apply and ensure any required tax return is filed correctly.

The key areas to remember are:

• Your tax year is split into resident and non-resident alien periods.
• Each period has different tax rules.

If you are uncertain about your tax status or how to file, we recommend speaking with a qualified tax adviser to ensure your return is completed accurately and correctly.

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