Is there any instace where a married couple living apart can be considered a legal seperation in California?

No. In order to qualify as a certified "legal separation" recognized by the State of California you need to officially file and obtain a Judgment of Legal Separation. Otherwise, to the State of California, you are still married and simply living apart. The fact that you are living apart may give rise to the fact that the two of you have established a 'date of separation' which is something each party needs to indicate in either a dissolution or a legal separation proceeding. However, identifying a 'date of separation' should not be confused with having the State of California consider a legal separation. Bottom line, even though you are living apart, it is not a 'legal separation' until a Judgment of Legal Separation is approved by the family court. This is not intended as legal advice and does not create an attorney-client relationship.

I am a Washington attorney and have no knowledge regarding the laws, rules or procedures in the State of CA. If your matter was taking place in WA, my response would be as follows: No. I recommend you confer with an experienced divorce attorney in your area. DISCLAIMER: This answer is provided for general educational purposes only. By using or participating in this site you agree and understand that there is no attorney client relationship between you and the attorney responding, and no attorney-client confidentiality. The law changes frequently, and varies from jurisdiction to jurisdiction. The information provided in this answer is general in nature and may not apply to the factual circumstances described in your question. The applicable law and the appropriate answer may be different in the State or States where the relevant facts occurred. For a definitive answer you should seek legal advice from an attorney who (1) is licensed to practice in the state which has jurisdiction; (2) has experience in the area of law you are asking about, and (3) has been retained as your attorney for representation or consultation. Your question and the attorney’s answer may be used for promotional or educational purposes.

You may be confusing "separation" with "legal separation". When a married couple live apart because one or the other (or both) of them communicated to the other that the marriage is over, that he or she is divorcing the other, or something substantially similar, the parties are "separated", i.e., the date of that communication would be the date of separation. A consequence of separation is that the earnings and accumulations of each party after the date of separation are the separate property of the respective party who earns and accumulates after separation. A "Legal Separation" is a proceeding essentially identical to a Dissolution of Marriage, where property is divided, child custody, child support, spousal support, and other issues get resolved pursuant to a Judgment, except for marital status - the parties remain married to each other, and if one of the parties to a "Legal Separation" decides that he or she wants to dissolve the remaining marriage (marital status), it would be necessary for that party to file and proceed with a separate Dissolution of Marriage case to Divorce his/her spouse.