Can a husband and wife operate as a Single Member LLC?

If a husband and a wife have joint ownership in a business in a community property state (Arizona, California, Idaho, Louisiana, Nevada, New Mexico, Texas, Washington & Wisconsin) they can qualify as a disregarded entity.

A business entity is a qualified entity if:

• the business entity is wholly owned by a husband and wife as community property under the laws of a state, a foreign country, or possession of the United States;
• No person other than one or both spouses would be considered an owner for federal tax purposes; and
• The business entity is not treated as a corporation under IRC §310.7701-2.
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Note: 

If an LLC is owned by husband and wife in a non-community property state, the LLC should file as a Partnership.  LLCs owned by a husband and wife are not eligible to be "qualified joint ventures" (which can elect not be treated as partnerships) because they are state law entities. For more information see Election for Husband and Wife Unincorporated Businesses.