SSI benefits and marriage

Yes, marriage may affect your SSI benefits, especially if your spouse brings in income of any form. Here is an excerpt from a 2008 report which investigated potential fraud regarding unreported marriages among SSI recipients :

The amount of a recipient's SSI payment is based on many factors, including marital status. Generally, SSA relies on SSI recipients to voluntarily report any changes in their marital status or living arrangements. For example, a marriage could affect the deeming of income from a spouse not receiving SSI to the SSI recipient. When both members of a couple receive SSI payments and live together, they receive a lower payment amount as a couple rather than as two individuals. When one individual receives SSI payments, the spouse's income-whether from earnings or OASDI benefits-is deemed available to meet the recipient's needs. Based on the amount, such income may reduce or eliminate the individual's SSI payments.

For SSI purposes, a marital relationship is one in which members of the opposite sex are legally married under the laws of the State where they have their permanent home or living together in the same household and holding themselves out as husband and wife to the community in which they live.

http://www.ssa.gov/oig/ADOBEPDF/audittxt/A-01-07-27109.htm