Short answer

If the person appointed to administer an estate (the executor or administrator) dies before finishing probate in California, the court will appoint a successor personal representative. You should immediately secure the estate, locate the will (if any), determine whether the will names a successor, and then file the correct petition in probate court asking the court to issue successor letters. You must follow California Probate Code procedures and provide required notices so administration can continue.

Detailed answer — step‑by‑step under California law

1. Confirm the status and secure the estate

First, determine whether letters testamentary or letters of administration were ever issued to the deceased administrator. If letters were issued, they may need to be formally closed or replaced. Immediately secure estate property: lock buildings, safeguard valuables, preserve business records, and prevent loss or waste of assets. If property is at risk or accounts are frozen, act quickly to protect value — but note that many financial institutions require court orders to release funds if the representative’s authority ended with their death.

2. Locate the will and read it for successor language

If the decedent left a will, find the original will. Many wills name an alternate or successor executor. If the will names a successor, that person can petition the court for letters and usually has priority for appointment.

3. Determine who has priority to be appointed

California uses a priority scheme for appointing personal representatives. A named successor in the will generally has priority. If there is no named successor, interested persons (heirs, beneficiaries, creditors in some cases) can petition. Anyone with an interest can ask the probate court to appoint a successor personal representative so administration can continue.

4. File the appropriate petition in probate court

You (or the person who will act) must file a petition with the probate court asking for appointment of a successor personal representative or issuance of new letters. The court will require notice to heirs and beneficiaries and may require a hearing. The local probate court clerk can provide the forms and filing procedure; California Courts provides probate forms and self‑help information online: California Courts — Probate Self‑Help. For statutory authority and procedures, see the California Probate Code (full code): California Probate Code (Legislature).

5. Bond, notice, and hearing

The court may require the successor to post a bond unless the will waives bond or the court dispenses with it. The successor must give notice to heirs, beneficiaries, and creditors according to probate rules. The court will set a hearing, and if everything is in order the court will issue new letters allowing the successor to act.

6. Continue administration tasks

Once the successor has letters, administration continues: inventory and appraisal of estate assets, paying valid debts and taxes, preparing accountings, and distributing assets to beneficiaries. Existing filings (inventory, petitions, bond) typically carry over, but the new personal representative must comply with all California Probate Code deadlines and court directions.

7. When there is no will or the will offers no successor

If the decedent died intestate (no valid will) or the will names no successor, an interested person must petition for appointment of an administrator. The court will appoint according to statutory priority among heirs. See California Probate Code and local court rules for details.

8. When to ask the court for emergency relief

If assets are at immediate risk (impending foreclosure, vanishing bank funds, perishable business inventory), you can ask the court for temporary emergency orders to preserve property before full appointment occurs.

9. Who may petition

Typical petitioners include the named successor in the will, the surviving spouse or domestic partner, adult heirs, and other persons with an interest in the estate. If multiple people petition, the court resolves competing claims based on priority, qualifications, and best interest of the estate.

Key California law references

Procedures for appointment and administration are governed by the California Probate Code and court rules. For the full statutes and procedures, consult the California Probate Code (Legislature): https://leginfo.legislature.ca.gov/faces/codesTOCSelected.xhtml?tocCode=PROB&tocTitle=+Probate+Code+-+PROB and the California Courts probate self‑help pages: https://www.courts.ca.gov/selfhelp-probate.htm. For probate forms, see: California Courts Forms — Probate.

Helpful hints

• Act quickly to secure and inventory assets. Preventable loss is the most common problem after a representative dies.
• Gather the original will, certified death certificate(s), bank statements, deeds, life insurance policies, and a current list of creditors and heirs before filing a petition.
• If the will names a successor, that person should file a petition for issuance of successor letters — this is usually faster than having a third party petition.
• Expect the court to require formal notice to heirs and beneficiaries. Plan for the time needed to serve notice and set hearings.
• If funds are urgently needed to pay mortgage, taxes, or preserve assets, ask the court for temporary authorization — courts can issue limited orders to allow necessary payments.
• Keep careful records of all estate actions and expenses; the successor will need to account to the court and beneficiaries.
• If the estate includes real estate, business interests, or contested creditor or beneficiary claims, consider consulting a probate attorney — these issues can be complex and affect timelines and costs.