How do Americans travel to the U.S. while being processed for CLN?

Everybody that has a U.S. passport, regardless of whether they have other passports or other nationalities, must use their U.S. passport to enter the United States. Of course, when an American changes citizenship, they can still enter the United States — albeit with a visa and a foreign passport. However, some people that travel a lot to the U.S. for business have asked if it's possible to travel to the U.S. after you've turned in your U.S. passport for processing and are awaiting a CLN (certificate of loss of nationality) but before before you've received your cancelled passport back from the U.S. State Department. After all, aren't you in a legal limbo, where you're still technically an American but you no longer have a U.S. passport (i.e. it's in the possession of the State Department in Washington, D.C. for processing)?

The answer is yes, you can travel to the U.S. during this time. What happens is after your final appointment at the U.S. Consulate/Embassy where you turn in your paperwork (the DS-4081, the DS-4082, the DS-4083, your U.S. passport book and/or your U.S. passport card), you will receive a letter signed by the consular officer on Embassy letterhead stating your situation and where your passport is, and it will be embossed with the embassy stamp. You will receive instructions that if you are asked as to whether you have a U.S. passport or U.S. citizenship, you are to answer "yes" and show them the letter to clear up any confusion. The letter does not look like a form, so the contents may vary depending on the embassy and officer, but my letter looked like this:

(This example letter is available in the Forms and Documents Page)

Being American, the letter (and forms) will be American "Letter" (8½ × 11 inch) size, so they won't fit with your file of A4 international standard paper. You'll probably want to take care of it, as it's a plain piece of paper that can soil and tear easily and will need to last you a few months while you travel.

On my version of the letter, they made a mistake and put "renunciation" instead of "relinquishment" (and they forgot to mention that I gave them both a passport book and a passport card), but this was corrected in the CLN and passport. It took about two and a half months to receive my CLN and cancelled passports in the postal mail. The embassy itself never notified me; I simply got the returned paperwork from the post office in standard mail sent directly from the U.S. Department of State in Washington D.C.

I had an opportunity to use this letter exactly once, when traveling through San Francisco International Airport. I got in the line for "Visitors" and not "U.S. citizens" because I figured this was the correct line if all I possessed was a foreign passport. The immigration officer who read the letter seemed more fascinated by it rather than suspicious of the letter or me. He had obviously never seen one before. He asked me a lot of questions about the contents. The most memorable question he asked me was "what happens if the State Department doesn't approve it?" I answered, "I think them stating that is more a formality than a possibility, but yes, that's a good question. I don't know." After holding up the line for a bit due to his curiosity, he was very helpful in describing how to use the ten-finger fingerprint machine as I had never used one before, then he welcomed me to the U.S. with a "Welcome to America" greeting — up until then, the immigration officers usually said "welcome home" to me.