如何申请访客签证延期您可以通过以下方式申请延长访客签证的期限。提交I-539表格，提供书面声明，其中包含适用限制的所有详细信息，并提供列出的支持文件。 表格I-539
申请访客签证延期的第一步是填写表格I-539，非移民签证延期。您可以在此处下载表格，并在此处查看有关如何填写表格I-539的提示。在此阶段，最好在网上提交I-539表格，因为许多实际的USCIS分支机构都已暂时关闭。书面声明
您必须包括书面声明（以信函形式），以说明您请求扩展的原因。例如，在这里您可以解释，由于COVID-19，您所在的国家/地区已经关闭了边界，在取消限制之前，您将不允许您返回。您可以在此处找到此信件格式的示例。其他证明文件
除了需要进行延期的原因外，USCIS还希望看到这样的事实，即您将尽可能返回自己的祖国。否则您将不会对国家造成经济负担（称为“ 公共收费”）。为了说明这一点，请在I-539表格中随附以下列出的支持文件。
Can B2 Visas be Extended During COVID-19?
As if worrying about your health, your family’s health, the crashing world economy, and being stuck in a foreign country isn’t enough, you are now also worrying about overstaying your visitor visa.
The good news is, if you find yourself in this uncertain situation, you can extend your B2 visitor visa. The USCIS allows for visitor’s visas to be extended due to the extreme and unusual situation created by the Coronavirus. This means you can remain legally in the U.S. borders until you are able to return home.
The extension of your visitor visa will, however, only be allowed where you are not able to travel back to your home country due to COVID-19.
So, how can you prove this is your case, and where can you apply for this extension? It’s actually quite easy.
How to File a Visitor Visa Extension
You can apply for an extension of your visitor visa by doing the following things. Filing a Form I-539, providing a written statement containing all the details of the restrictions that apply, and supplying the listed supporting documents.
Form I-539
The first step in filing for your visitor visa extension is to fill out the Form I-539, Extension of a Non-Immigrant Visa. You can download the form here and check out tips on how to fill out the Form I-539 here. At this stage, it would be best to file your Form I-539 online as many of the physical USCIS branches have temporarily closed.
Written Statement
You must include a written statement (in the form of a letter), which explains your reasons for requesting the extension. Here you can explain, for example, that your country has closed its borders due to COVID-19 and that you will not be allowed to travel back until the restrictions are lifted. You can find an example of the format of this letter here.
Other Supporting Documents
Over and above the reasons for your required extension, the USCIS also wants to see things like the fact that you will return to your home country once you can. Or that you won’t be a financial burden (known as a Public Charge) to the country. To show this, include the below listed supporting documents with your Form I-539.
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