In the late 1990s, Congress decided to punish foreign-born people who spend time in the United States unlawfully -- that is, without a visa, green card, or other official permission from the U.S. immigration authorities. Congress created a penalty that prevents people from coming or returning to the United States for three years or ten years, depending on how long they stayed unlawfully in the country. These are often referred to as the “time bars,” or the “three- and ten-year bars.” Although they are a big hurdle for many people, waivers (legal forgiveness) is available in certain situations.
An additional penalty (which we will not discuss further in this article) applies to people who lived in the United States unlawfully for more than a year and then left, or who were deported from the U.S., but who returned to the United States illegally (or were caught trying to). They can never get a green card or U.S. visa. This is usually referred to as the “permanent bar,” and no waiver is available.
If you spent time in the United States unlawfully at any time after April 1997, this article could be one of the most important for you to read and understand before you seek a U.S. green card or visa, no matter whether you are living inside our outside the U.S. now.
“Unlawful” is a difficult legal term. If you know that you were here in the U.S. without USCIS permission, it’s safe to say that your stay was unlawful. But the boundaries are less clear if, for example, you were waiting for USCIS to approve or deny an application you’d filed, were in removal (Immigration Court) proceedings, or had a visa but violated its rules. Student visa cases can be particularly tricky, because students are admitted for the "duration of status" -- that is, for as long as it takes them to complete their studies, instead of being given an exact expiration date on their U.S. stay. For issues such as these, you’ll need to consult an experienced immigration lawyer.

The Three- and Ten-Year Time Bars
The first thing to understand about the time bars is that (with rare exceptions) they are imposed only on people who are overseas and trying to return to the United States, not people who are already here and have the right to apply for their green card here.
Unfortunately, a number of people have no choice but to leave the U.S. and apply for their immigrant visa and green card through an overseas U.S. consulate, either because they are already overseas, or because they are in the United States but ineligible to use the U.S. green card application procedure called adjustment of status. (Adjustment of status is ordinarily available only to people who are in lawful status, or who entered the U.S. with inspection and are the immediate relatives of a U.S. citizen -- though exceptions to this rules exist.) If you are one of these people, the time bars could delay your immigrating to the United States as follows:
• Three Years. If you’ve spent more than 180 continuous days (approximately six months) in the United States unlawfully, you could be barred from coming back for three years.
• Ten Years. If you’ve spent more than one continuous year in the United States unlawfully, you could be barred from coming back for ten years.
In the past, applicants who left the United States to attend their immigrant visa interview at an overseas consulate may not have even known about the time bars before they left. This meant they could get all the way through receiving approval of their initial visa petition (Form I-130 or I-140), submitting follow-up paperwork, and getting an interview appointment -- only to leave the United States, attend the visa interview, and have the consular official inform them that although they would love to give the person a visa, the time bars prevent that person from actually reentering the United States for another three or ten years. Their only hope is to apply for a waiver of inadmissibility, as described below.
Fortunately, public awareness of this issue is increasing, and a new rule allows some applicants to apply for the waiver before, not after leaving the United States.

Loopholes in the Time Bar Law
Not everyone who has ever lived in the United States unlawfully will have a time bar problem. The law contains a few loopholes, as follows:
• Since the law didn’t go into effect until April 1, 1997, no unlawful time before that date counts.
• None of your unlawful time when you were under the age of 18 counts toward the three- and ten-year bars (though it does count toward the permanent bar).
• The law punishes only “continuous” presence, so a few months here and there don’t count, as long as no single stay lasted 180 days or more.

Waivers of the Time Bar Law
If you have a time bar problem, don’t give up yet -- especially if you are married to, or are the child of, a U.S. citizen or permanent resident. In that case, you are one of the lucky few who can ask for forgiveness, known in legal jargon as a waiver. But you’ll need a lawyer for this -- these waivers are not easy to get.
To be eligible, you will have to show that if you don’t get the visa, your U.S. spouse or parent will suffer extreme hardship. And when the immigration laws say “extreme” hardship, they mean it. The likely sadness that your spouse or parent will feel at your living thousands of miles away will not even begin to get your waiver application granted. An example of a case where the government would recognize extreme hardship is one where your spouse or parent has a severe medical problem and requires your constant attention. Financial hardship will also be taken into consideration.
Unfortunately, hardship that your U.S. citizen or permanent resident children, if any, would suffer does not count (although you could make an argument that their suffering would affect your U.S. citizen or permanent resident spouse or parent, emotionally, financially, or otherwise).
These time bars put visa applicants who must apply for their visas overseas at a disadvantage. But the critical point is that the time bars are not imposed on applicants who are within the United States, are eligible to get their green card by adjusting status here, and who do not leave. So if you are eligible to file your green card application (adjust status) in the United States, do so, and stay put until your application is granted.
And if you are living in the United States unlawfully but are not eligible to adjust status here, see a lawyer. The lawyer could advise you, for example, whether there is any new legislation pending that would expand the right to use the adjustment of status procedure; when and whether your spouse might be eligible for U.S. citizenship if he or she is now a permanent resident (which would help you if you had entered with a visa or on the Visa Waiver Progam, in which case you could adjust status); the current odds of being granted a waiver; and how and whether you can use the provisional waiver, instituted in 2013, which allows immediate relatives of U.S. citizens to request a waiver from USCIS after their I-130 has been approved but before their consular interview has been scheduled.”