If you are applying for a U.S. green card (lawful permanent residence) or other immigration benefit, and will be submitting your paperwork to an office in the United States, you will need to translate any non-English documents into English.
By way of example, you may need to provide such documents as your birth certificate, marriage certificate, school transcripts, letter from your overseas employer, lease or mortgage documents, letters between you and your U.S. citizen spouse (if you are applying for a green card based on marriage), and so forth. U.S. Citizenship and Immigration Services (USCIS) will not be able to understand these documents if they are not in English, and might therefore reject your application for lack of supporting evidence.
If you are submitting your paperwork to a U.S. consulate or embassy overseas, then the embassy or consulate may be able to handle documents that are in the language of that country. Their instructions will usually tell you if they cannot. Nevertheless, you should double check your local consulate’s procedures to be sure. To find contact and other relevant information for your local U.S. consulate, go to the "Websites of U.S. Embassies, Consulates, and Diplomatic Missions" page of the U.S. State Department's web site.
Here is how to create a translation that will satisfy the U.S. immigration authorities.
First, make a copy of the original document to submit to USCIS. The agency will want to see this even if it cannot understand what it says, to verify that the document has received all the appropriate government stamps (in the case of birth and marriage certificates) and otherwise looks authentic. Never send original documents to USCIS unless you’re willing to part with them forever, because you will not see them again. For example, you probably want to hang onto your birth certificate and marriage certificate.
You will next need to have someone prepare a certified, word-for-word translation of the document. Shortened summaries of the information in the document are not acceptable.
There is no need to spend a lot of money to obtain a professionally done translation. Any trustworthy friend who is fluent in both English and in the language of the document, and who is not your close relative, can do the certified translation. That person must, however, follow these instructions.
The person should write out a translation of the text, on a separate piece of paper, using a typewriter or word processor as opposed to writing by hand. The translator should add the following language at the bottom:
I certify that I am competent to translate from [the language of the document] to English and that the above [identify the document and to whom it pertains] is a correct and true translation to the best of my knowledge and belief.
Signed: [translator’s full name]
If you prefer, you can hire a professional, who should also add the same certification at the bottom of the translation. Or, if you hire an immigration lawyer, he or she may have a translator on staff who will do this for you.
For more information on the application process for U.S. immigration benefits, and how to avoid having your application rejected for careless entries or failure to submit all the required documents, see U.S. Immigration Made Easy, by Ilona Bray (Nolo).