Filing Form N-400, Application for Naturalization, is the first step toward becoming a U.S. citizen. But not every application ends with approval. Every year, thousands of applicants are denied because of errors, misunderstandings, or issues that could have been avoided.

While some denials are based on eligibility (serious criminal history or not meeting residency requirements), many others come down to preventable mistakes. For immigrants who have waited years for this moment, receiving a denial is heartbreaking — and in many cases, it could have been avoided with better preparation.

This page explains the most common reasons N-400 applications are denied, the mistakes people make when filling out the form, and how guided support can help reduce these risks.

How Common Are N-400 Denials?

USCIS receives hundreds of thousands of N-400 applications each year. Approval rates are high overall, but denials still happen regularly. According to USCIS statistics, roughly 10–12% of applicants are denied annually. That means tens of thousands of people each year walk away from their naturalization interview without the outcome they hoped for.

Most denials fall into two categories:

1. Eligibility issues – not meeting residency, continuous presence, or good moral character requirements.
   
2. Application errors or mistakes – incorrect information, missing documents, or inconsistent answers.
   

The good news is that many of the mistakes leading to denials can be prevented.

The Most Common Reasons for N-400 Denial

1. Not Meeting Residency or Presence Requirements

USCIS requires that applicants:

• Have 5 years of permanent residence (or 3 years if married to a U.S. citizen).
  
• Show continuous residence in the U.S.
  
• Be physically present for at least half of the required time.
  
  

Denials happen when applicants spend too much time outside the U.S., forget to track travel dates, or miscalculate time abroad. Something as simple as one long trip of 7 months can cause major problems if it is not explained properly.

2. Problems With Good Moral Character

Applicants must demonstrate good moral character during the statutory period. Denials often result from:

• Criminal history (DUIs, fraud, theft, domestic violence).
  
• Failure to pay taxes or file returns.
  
• Failure to pay child support or alimony.
  
• Dishonesty in immigration applications.
  

Even if the issue is from years ago, USCIS may still use it to deny your application.

3. Mistakes on the N-400 Form

The N-400 is 14 pages long and asks for extensive details: addresses, jobs, travel, marriages, children, and more. Common mistakes include:

• Forgetting addresses or employment history.
  
• Entering incorrect dates for travel abroad.
  
• Leaving sections blank.
  
• Inconsistent answers compared with past immigration forms.
  

USCIS officers compare the N-400 with previous applications (like your Green Card application). If information doesn’t match, they may question your honesty or deny your application.

4. Failing the Civics or English Test

Many applicants prepare for the civics test at the last minute or underestimate the English requirement. Denials occur when:

• Applicants fail the civics test twice.
  
• Applicants fail to show basic English reading and writing ability.
  

While exceptions exist for older applicants with long residency, most people must pass both tests to succeed.

5. Missed Appointments or Deadlines

Denials can also result from missing biometrics appointments, interviews, or deadlines to respond to Requests for Evidence (RFEs). Sometimes life gets in the way — work conflicts, family emergencies, or misunderstanding a USCIS notice — but unfortunately, missing an appointment can end your case.

6. Failure to Register for Selective Service

Men who lived in the U.S. between ages 18–25 are expected to register for Selective Service. If they did not, USCIS may consider it evidence of lacking good moral character. Applicants often discover this issue only when it’s too late.

7. Incomplete or Missing Documentation

Supporting documents are required to prove eligibility. Missing tax returns, Green Card copies, or marriage certificates can cause delays or denials. USCIS will sometimes issue an RFE, but in other cases, the application may be denied outright.

How Small Mistakes Become Big Problems

For many applicants, the biggest surprise is that small errors can create major consequences. Forgetting a short trip abroad or leaving a job off your history may seem harmless, but USCIS officers are trained to look for consistency. Incomplete or inconsistent answers can make it appear as if you are hiding information — even when the mistake was unintentional.

This is why so many applicants feel overwhelmed. The form is long, the details are exact, and the pressure of knowing that every answer matters can be intimidating.

Common Mistakes People Make on Their Own

When applicants prepare the N-400 without support, some of the most frequent mistakes include:

• Misunderstanding the difference between continuous residence and physical presence.
  
• Forgetting to include every child, even those living outside the U.S.
  
• Answering “yes” or “no” incorrectly to the long list of background questions.
  
• Submitting the wrong filing fee or missing biometric fees.
  
• Failing to prepare for the civics and English test until the last minute.
  

Any one of these errors can add months of delay — or worse, lead to denial.

How Our Service Helps Prevent Mistakes

While no one can guarantee approval, the best way to reduce the risk of denial is to file a complete, accurate, and consistent application. That is exactly what our service is built to provide.

Here’s how we help:

• Guided Questionnaire – Our online questionnaire is in English and Spanish, making it easier to answer accurately. We walk you through every question in plain language, so you don’t miss details.
  
• Form Preparation – We prepare your N-400 in the exact format USCIS requires, making sure it is consistent and complete.
  
• Optional Attorney Review – We offer attorney review of the whole package (N-400 and necessary documents) in order to ensure legal soundness before filing the Application for Naturalization.
  
• Interview Preparation – We prepare you for the Civics Test (English and Interview Preparation material coming soon!)
  
• Clear Instructions – We explain supporting documents and deadlines, so you don’t risk missing critical steps.
  
  

By choosing us, you minimize the chance of the small, avoidable mistakes that cause denials for so many applicants.

Can You Reapply After a Denial?

Yes, but it costs time and money. If your application is denied, you may reapply once you fix the issue — but you must pay the USCIS filing fee again, and in many cases, you must wait months before you can try again.

For applicants denied because of mistakes, this means losing hundreds of dollars and valuable time. Filing correctly the first time is the best way to avoid this setback.

Final Thoughts

The road to citizenship is challenging, and the N-400 application is full of opportunities for small errors to create big problems. While USCIS does not deny everyone, thousands of applicants each year receive denials for reasons that could have been avoided.

By understanding the most common reasons for denial — from travel mistakes to missing documents — and by filing with careful preparation, you can greatly reduce your risk.

You have worked hard to build a life in the United States. Don’t let preventable mistakes stand in the way of your citizenship. With the right guidance, you can file confidently, prepare thoroughly, and take your oath knowing you overcame the challenges the right way.