Naturalization Neighborhood Checks: What Letters to Include

On August 25, 2026, USCIS put a long-dormant power back into regular use. The Immigration and Nationality Act has allowed "personal investigations" of naturalization applicants since 1952: an investigator visits the area where you live or work and talks to people who know you. By 1991, the government had largely stopped doing them and relied on FBI background checks instead. The new Policy Manual guidance ends that general waiver.

That sounds more alarming than it needs to. The guidance also tells applicants how to make an investigation less likely, and it is specific about what helps. Facts are current as of September 23, 2026.

What a neighborhood investigation is

An investigation under INA 335(a) means a USCIS employee interviews witnesses about your conduct, residence, reputation and ties to the community. It can take place around:

your home or homes, and
your workplace, or your business if you are self-employed.

The investigator has to identify themselves as a USCIS employee to each witness, explain the purpose of the visit, and record the witness's identifying information. The Policy Manual tells investigators not to reveal derogatory information about you while asking around, and to gather facts rather than try to confirm a preconceived view. At a workplace, they might confirm with a supervisor, manager or coworker that you worked there, for the employer you named, for the period you listed.

The investigation should cover at least the five years before you filed, the same as the usual statutory period. USCIS can look at a shorter period for some applicants, such as spouses of U.S. citizens filing under the three-year rule, or a longer one, including time outside the United States, when it thinks that's necessary. If you have no stable address, for example because you live in a shelter, investigators may rely on records or letters from social workers, shelter staff or employers instead of neighbors.

Who gets one

The Policy Manual's starting point is that, unless waived, the investigation "applies to all aliens" applying for naturalization and is generally completed before the interview. In practice USCIS decides case by case, or by classes of cases, whether to conduct or waive it. The decision is made by USCIS's Fraud Detection and National Security Directorate with field operations. The guidance applies to applications pending on August 25, 2026 as well as new ones.

An investigation can also be requested later: an officer may ask for one at any point before you take the Oath of Allegiance, including after your interview, if questions or derogatory information come up.

What can lead to a waiver: reference letters

USCIS says it may waive the investigation if, for example, you submit enough testimonial or character reference letters. It specifically says that proactively submitting at least two letters with your Form N-400 can help it decide whether a waiver is appropriate. The letters are optional, and the guidance says the absence of letters alone doesn't justify finding that you lack good moral character. But it also says that not providing them "may contribute to a decision to conduct a neighborhood investigation."

Who should write them

The guidance prefers U.S. citizens who know you personally, such as neighbors, employers, coworkers and business associates. USCIS does not consider letters from your immediate family or other relatives.

What each letter should contain

According to the Policy Manual, each letter should include:

The writer's full name, address, phone number and email, plus a statement of their U.S. citizenship or immigration status and documentation of it, such as a copy of a passport page or naturalization certificate.
How the writer knows you, and for how long.
Specific examples or observations showing your honesty, integrity and involvement in the community.
An explicit statement about your moral character and your attitude toward the United States and the U.S. Constitution.

That last item is easy to leave out because it feels unusual to write. Leave it out and the letter doesn't cover everything the guidance lists.

What makes a letter useful

Officers are told to weigh each letter's credibility, detail and relevance. A few lines of praise won't do much. A neighbor of six years who describes how you organized the building's snow shoveling rota and looked after their cat when they were in hospital gives an officer something concrete. Each writer should describe what they have personally seen, in their own words. A stack of identical template letters is weaker than two genuine ones, and a letter that says something untrue is far worse than no letter.

Validation of what you wrote

The same update reinforces something that applies whether or not anyone visits your street: officers are expected to validate the information in your application, including residences, employment, education, family information, criminal history and immigration history. The guidance gives an example. If an applicant claims a degree and the officer finds the claim false, the officer then looks at whether the applicant got their green card using false information too.

The practical lesson is to make your N-400 match your records. Addresses, dates of employment and trips abroad should line up with what you told USCIS in earlier filings, or come with an explanation of why they don't. An honest correction is far better than an inconsistency an officer finds on their own.

If there is an investigation

If USCIS intends to deny your case based on something it learned in the investigation, it must tell you about the information and give you a chance to rebut it.
A person who doesn't like you doesn't decide your case. The officer weighs the credibility of what witnesses say.
If you are asked for more evidence to help decide whether to do an investigation, answer. The guidance says failing to reply may count toward a decision to conduct one.
Applicants naturalizing through military service have that service taken into account in the waiver decision.

If you have a complicated history, such as arrests, long trips abroad or gaps in your record, talk to an immigration attorney or DOJ-accredited representative before you file. That's also worth doing before the proposed fee increase pushes you to file in a hurry.

USCIS May Talk to Your Neighbors Before You Become a Citizen. Two Letters Can Help

What a neighborhood investigation is

Who gets one