Does having a will mean you can avoid probate? The answer is, unfortunately, no. Having a properly drafted and funded trust is the surest way to avoid probate.
However, having a will (testate) does result in some differences; and having a will is always preferable to not having a will (intestate). With regard to probate administration, having a will means that the Probate Court will know exactly who you want to handle your affairs, and how your want your debts and assets to be handled.
The first thing that happens upon your death is that your will gets lodged with the local Probate Court. The executor (the person nominated in your will to handle your estate when you die) will then petition the Probate Court to become your executor for the probate administration. Barring any objections and evidence of outrageous behavior by the nominated executor, the Probate Court will confirm your nominated individual as executor of your probate estate. This could make a big difference since, otherwise, anyone can petition to become your executor, and the Court will make the ultimate selection. Spouses, then children, are given preference. This could be particularly problematic if you are married, but have children from a prior relationship. In such an instance, you may want to nominate a neutral third party to be the executor, in order to keep any family conflicts at a minimum.
Having a will will also ensure that your wishes regarding your property (and remains) will be honored. California has its own intestate laws of heirship – meaning, if you die without a will, the laws of California will govern who gets what. These laws may directly conflict with your testamentary intentions. By having a will, you can specifically detail who you want to get what, and your executor will be obligated to follow those wishes (and the Probate Court will confirm they’re followed).
The other benefit of having a will is that you can nominate your Conservator, should it become necessary to have one. A Conservator is the person who, once confirmed by the Probate Court, will basically step into your shoes for every day decision making regarding your finances (Conservatorship of the estate), and for ensuring you get proper food, clothing, shelter, and health care (Conservatorship of the person). Absent a will, as with probate, anyone can petition to become your Conservator.