Yes. As of July 2013, same-sex marriage is legal in 13 states and the District of Columbia. Same-sex couples can now marry in California, Connecticut, Delaware, D.C., Iowa, Maine, Maryland, Massachusetts, Minnesota, New Hampshire, New York, Rhode Island, Vermont and Washington.
Many other states have passed laws specifically barring same-sex marriages. However, there are states that allow same-sex unions called "civil unions" or "domestic partnerships" that are similar to marriage and offer all or most of the benefits married couples receive.
Colorado, Hawaii, Illinois and New Jersey offer civil unions. Delaware, Rhode Island, Vermont, New Hampshire and Connecticut had civil unions, but with the legalization of same-sex marriage in each of these states, valid civil unions have been (or will be) merged or converted into marriages.
California, Oregon, Washington, Maine, Hawaii, D.C., and Nevada offer domestic partnerships. Rights and benefits for couples in domestic partnerships vary from state to state. Wisconsin offers a type of domestic partnership, but it's more akin to a registration for same-sex couples, which confers limited spousal rights.
If you are in a registered domestic partnership in California, the recent ruling legalizing same-sex marraige has no effect on your relationship status. Domestic partnership registrations are different from marriage licenses. The California Secretary of State’s Office will continue to process domestic partnership registrations and notices of termination of domestic partnerships.
In Washington state, any state registered same-sex domestic partnership, where neither party is sixty-two years of age or older, will be automatically converted into a marriage as of June 30, 2014.
For more information, see Nolo's article Same-Sex Marriage: Developments in the Law. For guidance on whether to enter into a marriage or other legal relationship with your same-sex partner, see Making It Legal: A Guide to Same-Sex Marriage, Domestic Partnerships & Civil Unions, by Frederick Hertz with Emily Doskow (Nolo).
A marriage license is a piece of paper that authorizes you to get married and a marriage certificate is a document that proves you are married.
Typically, couples obtain a marriage license, hold the wedding ceremony, and then have the person who performed the ceremony file a marriage certificate in the appropriate county office within a few days. (This may be the office of the county clerk, recorder or registrar, depending on where you live.) The married couple will be sent a certified copy of the marriage certificate within a few weeks after the marriage ceremony.
Most states require both spouses, along with the person who officiated and one or two witnesses, to sign the marriage certificate; often this is done just after the ceremony.
Usually, you may apply for a marriage license at any county clerk's office in the state where you want to be married. (In some circumstances, you must apply in the county or town where you intend to be married -- this depends on state law.) You'll probably have to pay a small fee for your license, and you may also have to wait a few days before it is issued.
In some states, even after you get your license you'll have to wait a short period of time -- one to three days -- before you tie the knot. In special circumstances, this waiting period can be waived. If you wait too long, your license will expire. Licenses are good for 30 days to one year, depending on the state. If your license expires before you get married, you can apply for a new one.
For more specific information about marriage license laws in your state, see Chart: State Marriage License and Blood Test Requirements.
A handful of states still require blood tests for couples planning to marry. Most do not. (For information on which states require them, see Chart: State Marriage License and Blood Test Requirements.
Premarital blood tests check for venereal disease or rubella. The tests may also disclose the presence of genetic disorders such as sickle-cell anemia or Tay-Sachs disease. You will not be tested for HIV, but in some states, the person who tests you will provide you with information about HIV and AIDS. In most states, blood tests can be waived for people over 50 and for other reasons, including pregnancy or sterility.
If either partner tests positive for a venereal disease, what happens depends on the state where you are marrying. Some states may refuse to issue you a marriage license. Other states may allow you to marry as long as you both know that the disease is present.
Non-religious ceremonies -- called civil ceremonies -- must be performed by a judge, justice of the peace, or court clerk who has legal authority to perform marriages, or by a person given temporary authority by a judge or court clerk to conduct a marriage ceremony. Religious ceremonies must be conducted by a clergy member (priest, minister, or rabbi). Native American weddings may be performed by a tribal chief or by another official, as designated by the tribe.
You must meet certain requirements in order to marry. These vary slightly from state to state, but generally include: