What should be done when a passport wasn't stamped on arrival in the US?
Recently, my wife and I entered the USA in Atlanta. We scanned our passport and visa, gave our fingerprints and had our photos taken at the kiosk. We received a receipt, which was given to an Immigration officer. He had us go through the Customs luggage check, after which our passports were returned to us.
Once we arrived home, we found that only one passport was stamped for admittance, one is not. What don't know whether this was just an oversight and we don't know what to do.
Do we need to return to the airport and have this corrected? If we don't do anything, will we have future problems exiting and re-entering the US?
If your online I-94 is correct, then I wouldn't worry too much. If your entry, however, has not been recorded, I would recommend going to the nearest CBP office to ensure correction of the record.
If any of you is a US citizen, that person needs no record of entry.
For foreigners, the entry should be electronically recorded and searcable on the I-94 Website. Thus, an entry stamp isn't really needed in practice these days, but if a foreigner doesn't get one, carrying a printout of the result page of the linked search, along with your passport, is a good idea in case you're stopped by the police, Immigration Enforcement or Border Patrol.
The info suggests that OP is a US resident which allows them to use the automated kiosk system, which documents their arrival.
@Giorgio those systems, or at least some of them, also process VWP and B-visa visitors.
I have Global Entry and don't usually get an entry stamp. Sometimes I've had an I-94 'receipt' print out, which I can choose to conserve, but the record is properly held by CBP and can be requested either through their website or by applying to them under Freedom of Information laws.
Much of what you say about "foreigners" is specific to non-residents. I am a foreigner, relative to the US, but use Global Entry kiosks and carry my green card in case I get stopped by the Border Patrol.
@Sam_Butler there is a law, seldom enforced but often invoked by Border Patrol to justify their demands that all aliens carry immigration documents, that says anyone who has been "registered and fingerprinted" must carry with them any "alien registration receipt" issued to them. Regulations define the creation of an electronic I-94 record as equivalent to issuing a registration receipt. It could be argued therefore, that you *should* "choose to conserve" those printouts, and if you don't get one, you should print one from the website. But in practice you're probably okay without one.