When you arrive at a US port of entry, you will be required to fill out Form I-94 and as an evidence of your admission, this form will be stamped by an immigration officer and stapled to your passport. The admission date and the expiration date of your stay will be stamped on this form and the arrival portion of the form will be retained by the immigration officer and the departure portion will be given to you. You need to keep the departure portion with you and it will be collected by the airline when you leave the United States.
The expiration date stamped on your Form I-94, is the date of expiration of your authorized period of stay and you can stay in America only until that date. It is illegal to remain in the country beyond that date and you will be deported from the country if you do so. Your Form I-94 must be valid and you must not let this form to expire and you need to keep the departure record in a safe place as you are likely to get into trouble if you lose it.
If you wish to stay back in the country for few more days beyond the date indicated on your departure record, you will have to file an application to extend your stay and you can do that by filing Form I-539. At the same time, if you lose your departure record while in America, you will have to apply for a replacement by filing Form I-102, Application for Replacement/Initial Non-immigrant Arrival-Departure Document. You can also file this form to replace a mutilated or a destroyed departure record.
You may not be able to extend your stay in the country, renew your visa or change your status, if you do not have a departure record. Hence, it is mandatory to get your departure record replaced, if you lose it. Likewise, you may not be granted entry into the country next time, if you leave the United States without your departure record. This departure record will help the customs officers to record your departure and if your departure is not recorded properly, you may encounter difficulties while trying to re-enter the United States. Hence, it is important to replace your Form I-94, if you lose it while in America and to get it replaced, you will have to file Form I-102, along with the form filing fee, $330.
Similar to the other immigration forms, this form must also be filed along with few supporting documents and a copy of your Form I-94, if you have one. You may submit a copy of your passport’s biographic page, if you do not have a copy of your departure record or some other evidence of your admission into America.