Basically, a legal separation is when a married couple makes a binding agreement about how to manage their affairs and assets while living apart, but do not get a formal divorce. The grounds and procedure for a legal separation are the same as those for divorce. The important thing to remember is that with a legal separation you are still legally married. You and your spouse must still agree on custody, property settlement, support and/or alimony, just as in a divorce. Legally separated couples may not remarry without first obtaining a divorce.
Another thing to consider is that the government considers you to be married. If you divorce after ten years of marriage, you may receive social security benefits based on your ex-spouse’s earnings. In a legal separation the tax, estate, and insurance consequences may differ from those of a divorce.
If, at any time after the legal separation, one spouse decides to get a divorce, a simple motion to the court along with an affidavit stating that the parties have not resumed marital relations, will convert a separation into a divorce without the participation of the other spouse. After the legal separation process has been completed, the court should not require the usual 90-day waiting period to grant a divorce.
Don't forget, if you are simply living apart, you are not legally separated regardless of the length of time. You do not have the benefits of any court orders and enforcing informal agreements may be difficult.
With that said, most courts have information centers with free how-to booklets on divorce.
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