10 Worst Mistakes You Can Make with Your Estate Planning

Short answer: The estate planning mistakes that do the most damage in California are ordinary ones: a trust that got signed but never funded, a plan nobody updated after a divorce or a new grandchild, no incapacity documents in place, and total silence with the family about what the plan says. Any one of these can push an estate into full probate, where the statutory fees alone run $23,000 to the executor and another $23,000 to the estate’s attorney on a $1,000,000 estate, under Probate Code §§ 10800 and 10810. Fixing these problems while you are alive and capable costs far less than untangling them in court after you are gone.

Why does an unfunded trust fail to do the one job it has?

A revocable living trust only avoids probate for assets that are actually retitled into it. Signing the trust document and leaving your house, bank accounts, and investment accounts in your own name accomplishes nothing on its own. If those assets are still titled in your individual name when you die, they are subject to probate regardless of what the trust document says, because a trust only controls what it actually owns.

California requires formal probate for an estate with assets subject to probate totaling more than $208,850 in gross value, for deaths on or after April 1, 2025, under Probate Code § 13100. On a $1,000,000 estate that lands in probate, the ordinary statutory fees are $23,000 to the executor and a separate $23,000 to the estate’s attorney under Probate Code §§ 10800 and 10810, before court costs or bond are added. That is the price of a trust that exists on paper but was never funded.

What happens when nobody updates the plan after a life change?

An estate plan signed years ago does not know about the divorce, the new spouse, the grandchild, or the house you sold and the one you bought since. Beneficiary designations on retirement accounts and life insurance control who receives that money regardless of what your will or trust says, so an outdated designation naming an ex-spouse can still hand that account to someone you no longer intend to benefit. Marriage, divorce, a birth, a death in the family, or a move to a new state are all reasons to pull the plan back out and read it again, not assume it still fits.

Why does skipping incapacity planning leave your family stuck?

Estate planning is not only about what happens after death. Without signed incapacity documents naming someone to act for you, a stroke, an accident, or a serious diagnosis can leave your family with no one legally authorized to pay your bills, manage your accounts, or speak with your doctors on your behalf. A durable power of attorney and a healthcare directive are the documents meant to fill that gap, and they only work if they are signed before the incapacity happens, not after.

What does staying silent about the plan cost your family later?

Families who never hear about the estate plan until after a death are the families most likely to end up in a dispute over it. A conversation about who is named executor or trustee, and roughly how the estate will be divided, heads off the “I didn’t know that was the plan” fights that consume time and money once someone has already died. The same logic applies to family dynamics generally: if you already know two of your children do not get along, or that a beneficiary has creditor or spending problems, the plan should account for that in advance rather than let the family discover it after the fact.

What else commonly gets missed: taxes, beneficiaries’ actual needs, and digital accounts?

A plan built only around your own current situation, without asking what each beneficiary actually needs, can hand a large lump sum to someone unequipped to manage it, or divide assets evenly in a way that ignores one heir’s disability, age, or financial circumstances. Separately, digital accounts, from email to financial apps to social media, do not disappear when you die, and someone needs both the legal authority and the practical information, meaning account lists and access instructions, to deal with them. Neither problem gets fixed by a generic form. Both take an actual conversation with whoever is putting the plan together, and for anything involving significant tax exposure, that conversation should include an accountant or estate planning attorney who can evaluate your specific numbers.

Figures verified July 2026.

What to do next

Pull out your existing will or estate plan, or admit you never got around to one, and read it with fresh eyes. If it does not name current beneficiaries, does not include signed incapacity documents, or you cannot say for certain whether your house and accounts were ever retitled into the trust, those are the gaps to close first. An estate planning attorney can usually confirm in one meeting whether your trust is actually funded and whether your documents still match your life as it is now, not as it was when you signed them.