To correctly complete your
Application for Naturalization (Form N-400), you will have to mention all your travels during the last five years outside the U.S. territory if they lasted more than 24 hours. You must not omit or “forget to mention” any of your travels, because if you do, USCIS may reject your application for naturalization.
There are several options for you to find all your trips outside the U.S. For starters, you can look for the departure and arrival stamps on your passport: all your travels are imprinted on passport pages. But what if you lost your passport?
If that is the case, you can visit the Customs and Border Protection (CBP) website to find the records: CBP has all the travel data. Alternatively, you can submit a FOIA (Freedom of Information Act) request to CBP to receive the data.
Sometimes not all your travel data may be available on the CBP website. You may need to contact the border controls where you entered the U.S. You can also contact airports or travel companies that you used. It is may be also worth asking your friends and relatives about your travels.
If you are not sure if CBP or your passport provide all the trips, you will still have to find the records to ensure your application will be accepted by USCIS.