It depends on a number of issues, including what account you use to purchase the property, whose names are on the papers, whose credit scores are used to calculate the interest rate, etc....but in short, DON'T - your wife can attempt to claim the house as joint property even if it is not because mere seperation does not provide legal coverage from 1/2 of everything in your marriage. Even if she fails, it can be used as extra leverage by her against you in mediation, or as food for thought by the Judge or jury deciding your eventual case.
Wait until the divorce is final before buying property. No matter what a good deal you are getting - do NOT sign until after the divorce! And, obviously, don't let your wife know about your impending purchase.
This answer is for information only and is not advice.
In most situations, the property would be considered community property. If you do a partition agreement or a Rule 11 agreement with your spouse, you can designate the property as your separate property and then it would not be subject to division upon divorce. You should probably include the downpayment funds and any money you spend on the house as your separate property as well, so there's no request for reimbursement during the divorce.
Using a bank account just in your name, and using just your personal credit, will not automatically remove the house from community property. More important is the source of the money you use. If the funds are your separate property, then the house may be able to be considered separate property, which removes it from the assets to be divided.
Because the house will be such a major investment for you, you should visit with a local attorney. Take your bank records so the attorney can review them and give you an opinion about whether the funds might qualify as separate property.
Both of the above answers are wrong IF you move out before you buy the new house. The community ends on the date of separation and admittedly there can be an argument about when that occurred. But after the date of separation anything you buy with your money is separate property. Period.
The last two answers are incorrect. The original question came from someone living in Forney, Texas, a small town just east of Dallas, Texas. I answered the question based on Texas law, which is different from California law. The community, in TEXAS, continues until the divorce is final, which is the date the final decree of divorce is signed by the judge, assuming there's no appeal or motion for new trial. I realize the rule is different in California, but the writer was from Texas and my answer is correct for Texas.
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