The law has not traditionally looked favorably upon individuals living together outside marriage. However, the law in this area has changed considerably in the past 40 years, and cohabitation has increased dramatically. In 1970, about 530,000 couples reportedly lived together outside marriage. This number increased to 1.6 million in 1980, 2.9 million in 1990, 4.2 million in 1998, and 5.5 million in 2000.
In some respects, unmarried cohabitation can be beneficial from a legal standpoint. Unmarried partners may define the terms of their relationship without being bound by marriage laws that can restrict the marriage relationship. When a relationship ends, unmarried cohabitants need not follow strict procedures to dissolve the living arrangement. Moreover, unmarried couples can avoid the so-called “marriage tax” in the Internal Revenue Code that provides a greater tax rate for unmarried couples than it does for two unmarried individuals (notwithstanding efforts to eliminate this penalty).
On the other hand, unmarried cohabitants do not enjoy the same rights as married individuals, particularly with respect to property acquired during a relationship. Marital property laws do not apply to unmarried couples, even in long-term relationships. Moreover, laws regarding distribution of property of one spouse to another at death do not apply to unmarried couples. Children of unmarried couples have traditionally not been afforded the same rights as children of married couples, though most of these laws have now been revised to avoid unfairness towards offspring.
A fairly recent trend among both heterosexual and homosexual couples who live together is to enter into contracts that provide rights to both parties that are similar to rights enjoyed by married couples. In fact, many family law experts now recommend that unmarried cohabitants enter into such arrangements. Further changes in the laws may also afford greater rights to unmarried partners who live together. However, such arrangements may be invalid in some states, particularly where the contract is based on the sexual relationship of the parties