If you're traveling to France for a short stay of less than 90 days over a period of six months for tourism or business, you do not need a visa if you're a U.S. citizen. The website of the French consulate in New York City provides a list of countries whose citizens do not require a visa for a short stay.
If you are intending to stay in France for a period of over 90 days, you need to apply for a long stay visa at your nearest French consulate. You will need the following: one filled-out long stay application form and one passport photograph and your U.S. passport (plus one photocopy of the identity and validity pages) valid for at least three months beyond the last day of your stay in France. The passport must have at least two blank visa pages left to affix the visa. The following documents must be submitted in the original with one set of copies and a French translation: one O.F.I.I. residence form, any relevant documents related to your present occupation in the U.S. (pay stubs for the last three months or a letter from your employer stating that you are on leave of absence, taking a sabbatical, or any other employment status); if you are retired, Social Security payment receipts; if you are self employed, a business license; a financial guarantee, such as an up-to-date bank statement showing that you have sufficient funds to live in France, or proof of retirement pension or personal income; proof of lodging in France, such as a lease, lease agreement or title deeds in France, or a certificate from a France resident stating that he or she will provide accommodation during your stay in France; a letter from an insurance company stating that you will have valid medical coverage in France; a letter of motivation explaining why you are applying for a long stay in France; and a written statement acknowledging that you will neither seek nor accept paid employment during your stay in France.
If the purpose of your trip to France is other than travel (study, work, etc.), then you will require a specialized visa. Some of the major French visa types for foreigners are as follows: student visas, au pair visas, work visas, visas for domestic staff, business permits for foreigners, visas for spouses of French and E.U. citizens. Each of these visas has its own application procedure.
