About Oath of Office
The person designated to serve in a probate estate position (executor, administrator, guardian, etc.) swears under oath that they will faithfully discharge the duties of that office.
When you'd use it: File this form when assuming any appointed or elected office role in a probate estate proceeding, typically at or shortly after the time of appointment.
Where to get the official form
The official version of Oath of Office is published as a PDF by the Illinois courts. We checked this link and it resolved to a form on an official court or government website — always download the current version directly from the source rather than a third-party copy:
Verified official PDF
Download Oath of Office (PDF) →
Source: mchenrycircuitclerk.org
Link last checked: May 31, 2026
How to file Oath of Office in Illinois
- Step 1 — Confirm you have the correct formUse Oath of Office (PR-OAT1) when file this form when assuming any appointed or elected office role in a probate estate proceeding, typically at or shortly after the time of appointment. Double-check it's the right form for your situation — Illinois probate forms are revised periodically, so verify the name and number against your court's current form list before you start.
- Step 2 — Complete every required fieldFill out Oath of Office carefully and review it for errors before filing. Probate cases can already take months — a small mistake on the form can set your timeline back further.
- Step 3 — Get it notarized or witnessed if requiredSome probate forms must be signed in front of a notary or witnesses. Check the instructions on the form itself, and arrange notarization before you file if it's required.
- Step 4 — File it with the correct courtSubmit Oath of Office to the probate court or county clerk handling the estate — usually in the Illinois county where the deceased lived. Ask the clerk how they prefer to receive filings (in person, by mail, or e-filing).