ITIN Application in the UK
Last updated September 03, 2026
Written by: Clark Stott
In this article
Can I get an ITIN when living in the UK?
Yes, as someone who needs to file a US tax return from the UK, you can apply for an ITIN. You need to complete Form W-7 and also have your identification, such as a valid British passport, verified, usually by an IRS-authorized Certifying Acceptance Agent (CAA).
What is an ITIN?
An ITIN, or Individual Taxpayer Identification Number, is a tax processing number issued by the Internal Revenue Service (IRS) in the United States.
It’s a nine-digit number that serves a purpose similar to a Social Security Number (SSN) but is used for individuals who are not eligible to obtain an SSN, such as non-resident aliens or their dependents and spouses
An ITIN is used for federal tax purposes. It does not provide immigration status, work authorization, or eligibility for Social Security benefits.
Who needs an ITIN in the UK?
In the UK, non US-citizens, as well as their dependents and spouses who are not eligible for a Social Security Number, may need an ITIN. This includes:
- Nonresident aliens who need to file a US federal tax return.
- Resident aliens who need to file a US federal tax return but aren’t eligible for an SSN.
- Certain spouses or dependents of US citizens or resident aliens.
- Nonresident aliens claiming certain US tax treaty benefits.
- Dependents or spouses of US citizens or resident aliens.
- Certain students, professors, or researchers who have a US federal tax filing requirement or qualify for an exception.
An ITIN isn’t needed if you’re eligible to obtain an SSN.
What is the purpose of an ITIN?
The primary purpose of an ITIN is to provide a US taxpayer identification number to people who have a federal tax purpose but aren’t eligible for an SSN.
Depending on your circumstances, an ITIN may be needed for:
- Filing a US federal tax return.
- Reporting US-source income.
- Claiming a tax refund where eligible.
- Claiming certain US tax treaty benefits.
- Meeting another federal tax reporting requirement covered by the IRS’s ITIN rules.
An ITIN is issued for federal tax purposes and shouldn’t be treated as a general form of US identification.
Do I need an ITIN if I am a UK resident and have US income?
Yes. If you are a UK resident and have income from the United States, you will need an Individual Taxpayer Identification Number (ITIN), since it is required for individuals who are obligated to file US tax returns or are eligible to receive certain US tax benefits but are not eligible for a Social Security Number (SSN).
How do I apply for an ITIN from the UK?
To apply for an ITIN from the UK, you need to complete Form W-7, “Application for IRS Individual Taxpayer Identification Number.” The form requires detailed personal information and must be submitted along with a US federal tax return, unless you meet an exception.
In most cases, your application package will include:
- A completed Form W-7.
- A US federal income tax return.
- Original identification documents or copies certified by the issuing agency.
You generally need to submit Form W-7 with your federal tax return unless you qualify for one of the exceptions listed in the Form W-7 instructions.
What are the required documents for an ITIN Application?
The required documents for an ITIN application typically include:
- A completed Form W-7.
- A US federal tax return, unless an IRS exception applies.
- Documents proving your identity and foreign status.
- Supporting documentation if you’re applying under an exception to the tax-return requirement.
A valid foreign passport is the only document that can generally establish both identity and foreign status on its own. If you don’t provide a passport, the IRS generally requires a combination of at least two other acceptable documents, with at least one containing a photograph.
Where do I submit my ITIN application?
If you’re applying from the UK, there are several ways to submit an ITIN application:
- Mail your application to the IRS: Send Form W-7, your federal tax return where required, and original or issuing-agency-certified supporting documents to the IRS ITIN Operation.
- Use an IRS-authorized Certifying Acceptance Agent: A CAA can review and authenticate eligible identity documents, which can help you avoid sending your original passport to the IRS.
- Use an online CAA service: For example, Expat Tax Online can assist with the process so you don’t have to send your passport to the IRS.
- Visit an IRS Taxpayer Assistance Center: This is an option if you’re physically in the United States and make an appointment at a participating location.
For someone applying while remaining in the UK, mailing the application or working with an IRS-authorized CAA are generally the most practical options.
What’s the processing time for ITIN applications?
The processing time for an Individual Taxpayer Identification Number (ITIN) application can vary, but typically it takes about 7 weeks. However, this timeframe may extend to 9 to 11 weeks if the application is submitted during peak tax season or if it’s sent from overseas, such as from the UK.
How long does it take to get an ITIN from the UK?
When applying for an ITIN from the UK, you should generally anticipate a slightly longer processing time. On average, it can take up to 11 weeks, especially if additional documentation is required or during high-demand periods like the US tax season.
Note: Incomplete applications or requests for additional information can cause further delays.
Need to apply for an ITIN?
We’re IRS authorized to help you get it.
How much does it cost to apply for an ITIN?
There is no fee charged by the IRS for processing an ITIN application (Form W-7). However, if you choose to use the services of a professional, such as a Certifying Acceptance Agent or a tax advisor, their fees will vary based on the services provided.
Can a tax professional assist me with my ITIN application?
Yes, a tax professional can significantly assist with your ITIN application. They can provide guidance on the necessary documentation, ensure the application is filled out correctly, and help navigate any complexities, especially for those living in the UK. Their expertise can be invaluable in avoiding common pitfalls and ensuring a smooth application process.
An IRS-authorized Certifying Acceptance Agent can provide additional assistance by reviewing and authenticating eligible identity documents. This can be particularly useful for UK applicants who don’t want to send an original passport to the IRS.
What happens if I don’t have an ITIN but need to file US taxes?
If you are required to file US taxes and don’t have an Individual Taxpayer Identification Number (ITIN), it’s important to apply for one as soon as possible. Without an ITIN, you won’t be able to file your US tax returns, which could lead to delays in processing and potential penalties. The IRS requires an ITIN for individuals who are ineligible for a Social Security Number but still have a US tax filing or reporting requirement.
How can I check the status of my ITIN application?
The IRS recommends waiting for its standard processing timeframe before checking your application status. That’s generally 7 weeks, or 9 to 11 weeks if you applied from overseas or during peak tax season.
If you haven’t received an ITIN or correspondence after that period, you can contact the IRS:
1-800-829-1040 — within the United States
1-267-941-1000 — outside the United States; this is not a toll-free number.
This service allows you to inquire about the current status of your application approximately seven weeks after you have submitted it. When calling, it’s helpful to have a copy of your ITIN application and any other correspondence from the IRS handy for reference.
How do I renew my ITIN?
ITINs need to be renewed if they have not been used on a federal tax return at least once in the last three consecutive years or if the ITIN is included in the IRS’s list of expiring ITINs. To renew your ITIN, you will need to complete Form W-7, following the same process as the initial application.
Remember to include the required original identification documents or copies certified by the issuing agency, together with any other documents required by the current renewal instructions.
For those residing in the UK, the ITIN process can be complex. It’s often advisable to seek assistance from a tax professional who can guide you through the application or renewal process, help check the status of your application, and ensure that you remain compliant with US tax laws.
Frequently Asked Questions
Can I apply for an ITIN without sending my passport to the IRS?
Yes. One option is to work with an IRS-authorized Certifying Acceptance Agent (CAA). A CAA can authenticate certain identification documents and submit certified copies with your application, allowing you to keep your original passport rather than mailing it to the IRS.
Can I apply for an ITIN before I need to file a US tax return?
Usually, you apply for an ITIN when you have a federal tax filing or reporting requirement. Form W-7 is generally submitted with your US federal tax return unless you qualify for one of the IRS exceptions that allow you to apply without attaching a return.
Does having an ITIN make me a US tax resident?
No. An ITIN is a tax processing number and does not determine your US tax residency or immigration status. Your US tax status depends on separate tax rules and your individual circumstances.
Can I use an ITIN instead of an SSN if I’m eligible for an SSN?
No. The IRS issues ITINs only to people who need a US taxpayer identification number for federal tax purposes but aren’t eligible for a Social Security Number. If you’re eligible for an SSN, you generally shouldn’t apply for an ITIN.
What should I do if my ITIN application is rejected?
First, check the IRS notice explaining why the application wasn’t accepted. Common issues can involve incomplete Form W-7 information, insufficient supporting documentation, or problems establishing the applicant’s identity or foreign status. Depending on the reason, you may need to correct the application or provide additional documentation before resubmitting it.
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Clark Stott has been with Expat Tax Online since 2015. Being a dual national based in the UK, Clark has unique experience helping US citizens (and Accidental Americans) become tax compliant via the Streamlined Tax Amnesty program. Clark likes to help Americans in the UK keep their tax situations as simple as possible to avoid harsh IRS treatment.
