Your credit scores will not merge when you get married. Your credit score is supposed to remain your personal one and should stay separate from your spouse’s credit rating. However note that credit providers may look at dual income, which can make it easier to apply for a loan.
Will marriage in community of property affect my credit rating?
Yes most definitely. If you are married in community of property. If you are married in community of property and apply new credit or already have existing debt your spouse are jointly and severally liable for the debt incurred (before or after marriage). This means that both of you will be equally and fully (100%) liable for the debt of the other spouse. It means that a creditor may pursue a debt obligation against either one of the spouses or both until the debt has been paid in full. If you do not have enough money or assets to pay that debt, your spouse must make up the difference. Because the parties will be jointly and severally liable the creditors will rather target the more affluent spouses’ income or capital. A bad credit record of a spouse married in community of property will negatively affect the credit score of the other spouse.
This may seem unfair but unfortunately it's the law if you are bold or unwise enough to get married in community of property.