How to Apply for an ITIN 2026: A Guide for Germans
Christian··5 min read
There are a few hurdles on the road to the US credit system that feel bigger than they actually are. The ITIN application is one of them. Not because the process is particularly complicated, but because the information out there is poor. Official IRS pages are tailored to American taxpayers. German tax advisors often don't know the topic. And forums are full of half-truths that are three years old and no longer accurate.
I've been through the process myself. What I'm writing here is based on my own experience and what I've since heard from other Germans who've taken the same path. No hearsay, no theory.
What an ITIN Is and Why You Need One
ITIN stands for Individual Taxpayer Identification Number. It's a nine-digit number issued by the IRS (Internal Revenue Service, the US tax authority) to people who don't have a Social Security Number but need an identification number for tax purposes.
Important to understand: An ITIN is not a Social Security Number. It doesn't give you the right to work, no residency rights, and no social security benefits in the US. It is purely a tax identification number.
For Germans looking to build a US credit history, the ITIN is the key. Without it, you can't apply for a personal credit card in the US. Some banks accept the EIN (Employer Identification Number) of your LLC for business credit cards, but for personal cards, and thus for building a personal credit history, you need the ITIN.
The typical path looks like this: You set up a US LLC, apply for the EIN for the company, and then apply for the ITIN for yourself personally. The LLC isn't just a means to an end. It gives you a tax-related reason for the ITIN application, and without such a reason, the application will be rejected.
Why the ITIN Is So Important
The ITIN is more than a number on a piece of paper. It's your ticket into the US credit system. And that system works fundamentally differently from the German one.
In Germany, you have a Schufa score. Banks look at your entries, and if nothing negative shows up, you get a modest credit card limit. In the US, you have a credit score, a numerical value between 300 and 850 that builds over time. The higher the score, the better the terms you get.
The problem: Without an ITIN, there is no credit score. And without a credit score, there's no access to the credit cards that make the US system so attractive. The welcome bonuses, the high limits, the transfer partners, all of that remains locked until you have a number under which your credit history can run.
So the ITIN is the first real step. Everything before it, the LLC formation, the EIN, those are prerequisites. But the ITIN is what makes it all usable.
The Three Paths to an ITIN
There are three ways to apply for an ITIN. All three are legal and official. But they differ significantly in effort, risk, and convenience.
Path 1: Certified Acceptance Agent (CAA)
A CAA is a person or organization authorized by the IRS to accept ITIN applications and verify the applicant's identity. It sounds bureaucratic, and it is. But it's by far the best option.
The key advantage: You don't have to send in your passport. The CAA reviews your original document on-site, creates a certified copy, and submits it along with the application to the IRS. Your passport stays with you.
That's a huge difference compared to the other two paths. Anyone who's ever had to send their passport to a government agency for several weeks knows how uncomfortable that is. Especially when you need to travel in the meantime or need the passport as an ID document.
On top of that, there's professional guidance. A good CAA has been through the process hundreds of times. They know the typical mistakes, the most common reasons for rejection, and the current IRS requirements. You're not filling out the form alone and hoping it works. You have someone reviewing the application before it goes out.
Path 2: Directly by Mail to the IRS
You can fill out the W-7 form yourself and send it directly to the IRS along with your original passport (or a notarized copy). The form is available on the IRS website, and the mailing address is in the instructions.
The advantages: It costs nothing besides postage. You don't need an appointment.
The disadvantages: You have to send in your passport. Not a copy, not a scan, the original. Or a notarized copy that meets the strict IRS requirements. German notaries are often unfamiliar with these requirements, and an incorrectly notarized copy leads to rejection.
The IRS states that it will return the passport after processing. That's true. But the processing time plus transit means your passport can be gone for six to ten weeks. For frequent travelers, that's not an option.
Then there's the risk of errors on the form. The W-7 isn't a particularly long form, but the details are tricky. Wrong tax reason, missing checkbox, incomplete address, and the application gets rejected. Then the process starts all over again.
Path 3: At a US Consulate
In theory, you can also submit your ITIN application through a US consulate or the US embassy. In practice, this path is impractical for most Germans.
The consulates don't offer this service permanently. There are specific time windows, and appointments are limited. You have to appear in person, which depending on where you live can mean a significant trip. And the experience reports I've heard suggest that the consulate route is no faster than mailing it yourself.
This path can make sense if you already have an appointment at the consulate or live nearby. For most people, though, it's unnecessarily complicated.
Why the CAA Is the Best Path
I'll say this without qualification: If you're a German looking to apply for an ITIN, use a CAA.
Here's a summary of the reasons:
Your passport stays with you. That alone was the deciding factor for me. I travel frequently, sometimes on short notice. Giving up my passport for two months would not have been feasible for me.
Professional review. The CAA knows the current requirements. Forms change, guidelines get updated. What was correct last year might be wrong this year. A CAA who regularly submits ITIN applications is up to date.
Higher success rate. Self-filed applications have a significantly higher rejection rate than applications submitted through a CAA. A rejection doesn't just cost you time, it delays your entire timeline for building US credit.
Faster processing. CAA applications tend to be processed faster by the IRS than individual applications. That's because they're typically error-free and complete, which reduces the review effort on the IRS's end.
The only drawback: It costs money. More on that shortly.
Which CAAs Are Available in Germany
This is where options get thin. There are only a few certified Acceptance Agents in Germany, and most are based in Frankfurt or Munich. That's because the ITIN application is a niche topic. The demand isn't large enough to justify a CAA in every city.
As of 2026, here are the options:
Tax advisory firms with CAA certification. Some internationally oriented tax advisory firms in Frankfurt and Munich hold CAA certification. They often offer the ITIN application as part of a larger package, together with LLC formation and US tax filing. That can make sense if you want the entire process handled by one provider.
Specialized service providers. There are companies that specialize in assisting non-US citizens with the US tax system. Some offer CAA services remotely as well: you send your documents, schedule a video call for the identity verification, and the CAA handles the rest. However, the identity verification must be done in person; a purely remote process is not permitted. Some CAAs therefore offer appointments in various cities.
CAAs abroad. Alternatively, there are CAAs in other European cities, such as London or Amsterdam, and of course in the US itself. If you're planning a trip to the US anyway, you can schedule the appointment there. Cities like Miami, New York, or Los Angeles have significantly more CAAs than all of Germany combined.
The IRS maintains a list of all certified Acceptance Agents on its website. You can filter by country and city. I recommend using that list as a starting point and then reaching out directly.
One note: Not everyone who markets themselves online as an "ITIN advisor" or "ITIN service" is a certified CAA. There are intermediaries who fill out the application for you but can't actually submit it themselves. The difference matters: Only a certified CAA can verify your passport and create an accepted copy. Always ask for the CAA certification number.
The Process Step by Step
Here's the complete process as I experienced it and as it works in most cases.
Step 1: Clarify Prerequisites
Before you apply for the ITIN, you need a tax-related reason. The IRS doesn't issue ITINs simply on request. You have to demonstrate why you need a US tax number.
For most Germans who want to build US credit, the reason is a US LLC. If you own an LLC, you're liable for taxes in the US as the owner (even though the tax burden is often zero because the LLC is treated as a disregarded entity). This tax obligation is your reason for the ITIN.
Specifically, you need:
- An established US LLC with an EIN
- The intent to file a US tax return (or the obligation to do so)
- Your valid passport
If you don't have an LLC yet, the first step is forming one. That's a topic of its own, but in short: An LLC in Wyoming, Delaware, or Florida can be formed online within a few days, and you can get the EIN from the IRS for free, often even instantly by phone or online.
Step 2: Fill Out the W-7 Form
The W-7 is the official application form for the ITIN. It's two pages long and looks straightforward at first glance. On a second look, the details are where it gets tricky.
The key fields:
Reason you are submitting Form W-7. This is where you specify the tax-related reason. For LLC owners, this is typically Box "a" (Nonresident alien filing a U.S. tax return) or one of the Exception boxes. Which one is correct depends on your situation. A CAA is a big help here, because the wrong checkbox means rejection.
The most common approach for Germans with an LLC: You check the Exception that applies to partners of a US partnership or owners of an LLC. The LLC is treated as a disregarded entity for tax purposes, and as a single-member LLC owner, you're personally liable for taxes. That's the reason the IRS accepts.
Name and address. Sounds trivial, but it isn't always. Your name must be spelled exactly as it appears in your passport. Umlauts can be problematic. Some CAAs recommend spelling without umlauts (ae, oe, ue), others recommend keeping them. The address is your German address, since you're a non-resident.
Foreign Tax Identifying Number. This is where your German tax ID goes, the eleven-digit number you'll find on your tax assessment notice.
Step 3: Gather Your Documents
In addition to the completed W-7, you need:
Passport. The most important document. The passport must be valid. If you go through a CAA, the passport is verified on-site and a certified copy is created. If you submit the application yourself, you must send either the original or a notarized copy.
Proof of tax-related reason. Typically, the formation documents for your LLC (Articles of Organization) and the EIN confirmation (Letter 147C or CP 575). Depending on the situation, the IRS may request additional documents.
Tax return. In many cases, the ITIN application must be submitted together with a US tax return. For LLC owners, this is typically Form 1040-NR (Nonresident Alien Income Tax Return). Here too: A CAA or a tax advisor specializing in US tax law can tell you which forms are needed in your case.
Sometimes it's possible to apply for the ITIN under an Exception without simultaneously filing a tax return. That depends on the type of your LLC and your tax situation. It's one of the areas where the CAA pays for itself, because they know the current IRS practice.
Step 4: Appointment with the CAA
If you go the CAA route, you schedule an appointment. You bring your passport and all other documents to the appointment. The CAA verifies your identity, checks the documents, and creates the certified copy of your passport.
Typically, you'll go through the W-7 form together. The CAA checks whether all information is correct, whether the right tax reason is stated, and whether the supporting documents are complete.
The appointment itself usually takes 30 to 60 minutes. After that, the CAA handles the submission to the IRS.
Step 5: Wait
After submission, the waiting period begins. The IRS officially quotes a processing time of seven weeks. In practice, it often takes longer, especially in the months following April 15 (the US tax deadline), when the IRS is flooded with tax returns.
My experience: It took just under six weeks from the submission date to receiving the ITIN notice. Others report eight, ten, or even twelve weeks. There's no express service and no way to speed up the process.
You can check the status of your application by phone with the IRS. The number is the general IRS hotline, and wait times can be substantial. My advice: Don't call before six weeks have passed. Before that, nobody can tell you anything.
Step 6: Receive Your ITIN
The ITIN arrives by mail. You'll receive a letter from the IRS (Notice CP 565) containing your ITIN. Keep this letter in a safe place. You'll need the number for all subsequent steps: credit card applications, tax returns, bank accounts.
The ITIN format is 9XX-XX-XXXX. The first digit is always a 9. This visually distinguishes it from a Social Security Number, which never starts with 9.
The Costs
The ITIN itself is free. The IRS charges no fee for issuance.
The costs come from the path you choose:
CAA fee. Most CAAs in Germany charge between 200 and 400 euros for the ITIN application. Some offer packages that include the ITIN together with the tax return or LLC formation. In those cases, the ITIN portion is often cheaper because it's priced as an add-on service.
By mail yourself. Essentially free. You pay postage for registered mail to the US (about 10 to 15 euros) and possibly the notarized certification of your passport copy (30 to 80 euros at the notary). This saves money but costs you peace of mind and certainty.
Through the consulate. No direct fees for the ITIN service, but possibly costs for the appointment and travel.
My assessment: The 200 to 400 euros for a CAA is money well spent. The process is safer, faster, and less stressful. Compared to the total costs of building US credit (LLC formation, Registered Agent, tax return), the CAA is a manageable expense.
Common Mistakes and How to Avoid Them
Over the past few years, I've spoken with quite a few people who had problems with their ITIN application. The mistakes keep repeating.
Wrong Tax Reason
The most common mistake. You check the wrong reason on the W-7, and the IRS rejects the application. Especially prevalent: Germans who try to apply for an ITIN without an LLC or without a tax obligation. That doesn't work. The IRS doesn't issue ITINs on a speculative basis. You need a concrete, current reason.
Missing or Incorrect Supporting Documents
The second most common mistake. The W-7 is correctly filled out, but the supporting documents are missing or don't meet the requirements. Notarized certifications are a particular problem: German notaries are often unfamiliar with the specific IRS requirements, and a certification that's correct under German law will still be rejected by the IRS.
Name Discrepancies
Your name on the W-7 must exactly match the name in your passport. Sounds obvious, but: How do you spell umlauts? Do you have a middle name that's in your passport but you never use? Are there hyphens in your last name? Any discrepancy can lead to rejection.
Application Without a Tax Return
In many cases, the ITIN application must be submitted together with a tax return. Anyone who submits the application without the required tax return gets a rejection. There are Exceptions where no tax return is needed, but whether your situation qualifies should be clarified beforehand.
Applying Too Early or Too Late
Some people apply for the ITIN before they've formed their LLC. That doesn't work because the tax reason is missing. Others wait too long and miss the deadline for their first tax return. The best time to apply for the ITIN is shortly after receiving the EIN, when the LLC is established and the formation documents are available.
What Happens After You Receive It
You have your ITIN. What now?
Apply for a US Credit Card
The ITIN is the prerequisite for personal credit cards in the US. With it, you can apply for your first US credit card. The entry point is typically a secured credit card, where you deposit a security amount that also serves as your credit limit.
Popular options for getting started include the Capital One Platinum Secured or similar starter cards. Some banks, like Chase with the Chase Sapphire, require an existing credit score, which can be a problem for first-time applicants. Others, like Capital One, are known for accepting applicants without any credit history.
Build Your Credit Score
After about six months with an actively used US credit card, your first FICO score is generated. It typically falls between 680 and 700, which already counts as a "good" score. From this point, the doors open to better cards: Amex Platinum, Chase Sapphire Preferred, Capital One Venture, and many more. If you're already an Amex customer in Germany, you can also use the Amex Global Transfer.
Building a solid credit history takes time. But the ITIN is the starting point, without which nothing works.
File a Tax Return
With the ITIN, you're able (and often required) to file a US tax return. Even if your LLC has generated no profit, even if the tax liability is zero. Filing the tax return keeps your ITIN active and is part of the overall strategy.
ITIN Renewal
An important point that many people forget: The ITIN expires if it hasn't been used on a US tax return for three consecutive tax years. That means: If you receive your ITIN and then don't file a tax return for three years, the number gets deactivated.
Renewal is possible, but it takes time and effort. You have to fill out the W-7 form again, this time with a "Renewal" note, and submit the same documents as with the initial application.
My advice: File a US tax return every year, even if there's no tax obligation. This keeps your ITIN active, requires minimal effort (a tax advisor can handle a zero return in minutes), and avoids the renewal process.
Additionally, there's a renewal rule based on the year of issuance. In recent years, the IRS has called up ITINs for renewal on a specific schedule based on the middle digits. If your ITIN is due for renewal, you'll typically receive a letter from the IRS. But relying on that is risky. Better to actively use the ITIN every year.
My Experience with the Process
I went the CAA route. The appointment was in Frankfurt, at a tax advisory firm specializing in US tax law. The cost was 350 euros for the ITIN application, including review of the W-7 form and identity verification.
The appointment itself was straightforward. I had my documents with me: passport, LLC formation documents, EIN confirmation. The advisor walked through the W-7 with me, made a few corrections (I hadn't optimally stated the tax reason), and created the certified passport copy.
After the appointment, I had nothing left to do. The CAA submitted the application and sent me a copy by email.
Six weeks later, the letter from the IRS arrived. My ITIN was in it, along with a brief letter confirming the number. No congratulations, no welcome, just the number. Pragmatically American.
What surprised me most in hindsight: how easy the process is with the right guidance. I had put it off for months because I thought it would be a bureaucratic nightmare. In reality, it was one appointment, a bit of paperwork, and six weeks of waiting.
If I had submitted the application by mail myself, it probably would have worked too. But I would have had to send in my passport, I probably would have made a mistake with the tax reason, and the processing time would have been longer. The 350 euros for the CAA was by far the best investment in the entire US credit-building process.
The Timeline at a Glance
For everyone planning the process, here's the realistic timeline:
Week 0: Appointment with the CAA. Review documents, fill out the W-7, verify identity, submit the application.
Week 1-2: Application reaches the IRS. Intake process begins.
Week 3-6: Processing by the IRS. No updates during this time.
Week 6-8: ITIN is delivered. In some cases, it takes until week 10 or 12.
Week 8-10: Apply for your first US credit card. Open an account, apply for a secured card.
Month 6-8 after receiving the card: First FICO score is generated.
Overall, you should plan for about nine to twelve months from the first CAA appointment to your first FICO score. That sounds long, but it's a realistic timeframe. Planning for less puts you under unnecessary time pressure.
Tax Implications
An ITIN and a US LLC have tax consequences that go beyond the scope of this article. But here are a few points you should know:
CFC taxation. As a German tax resident, you may have to pay taxes in Germany on the profits of your US LLC under certain circumstances, even if you don't withdraw them. The details depend on the type of income and the structure of your LLC. A tax advisor with experience in international tax law is essential here.
Double taxation agreement. Germany and the US have a double taxation agreement that governs taxation. In many cases, a single-member LLC without active US business operations results in no or only minimal US tax liability. But this needs to be assessed individually.
Annual tax return. With an ITIN, you are generally required to file a US tax return annually. The cost for this with a specialized tax advisor ranges from 300 to 800 euros per year, depending on complexity.
This article is not tax advice. It's an experience report with practical tips. For your individual situation, you need a tax advisor who knows both German and US tax law.
Summary
The ITIN is the key to the US credit system. Without it, there's no access to personal credit cards and thus no building a personal credit history.
The best path to the ITIN is through a Certified Acceptance Agent. The cost of 200 to 400 euros is reasonable, the process is safe, and you keep your passport. The CAA appointment is one morning. After that, you wait six to eight weeks for the notice.
The most common mistakes are avoidable: state the right tax reason, submit complete documents, spell names correctly. A good CAA catches these errors before they become problems.
After receiving the ITIN, the real building begins: first credit card, generate a credit score, apply for better cards. The ITIN is not the goal. It's the beginning. But without this beginning, nothing happens.
If you've been putting off the process: I understand. I did it myself. But in hindsight, it was easier than expected. One appointment, a few documents, some patience. And then the door to the US credit system is open.