Legal Question in Real Estate Law in California

Yes, it's legal. However, there is sometimes a difference between what's legal and what's acceptable to the paper-pushers at mortgage or escrow companies, so my advice would be to explain what you're doing and why. They may ask you to sign both names or indicate that you have an "also known as" or "formerly known as."

The law generally allows people to use former names and even nicknames so long as the purpose is not to commit a fraud. In the case of birth (maiden) names, there is even some special statutory language allowing a married person to continue to use her (or his) birth or maiden name and requiring anyone doing business with her to accept her/his use thereof...... it is Code of Civil Procedure section 1279.6.

Keep in mind that when you pay off the loan or sell the property, perhaps many years from now, you will have to make reference to your former name, under which you incurred the debt or took title, in order for the county recorder to record and index the new documents so as to match the old documents. This requirement is set forth in the Civil Code, section 1096.