Sean Kotaro O'Neill is an American diplomat and the United States Ambassador to Thailand since February 2026.[2][3][4] O'Neill is a career member of the Senior Foreign Service, and he had served as Senior Bureau Official for the US State Department's Bureau of East Asian and Pacific Affairs.[2]
Sean O'Neill | |
|---|---|
 | |
| United States Ambassador to Thailand | |
| Assumed office February 11, 2026[1] | |
| President | Donald Trump |
| Preceded by | Robert F. Godec |
| Personal details | |
| Spouse | Sachiyo Kubo |
| Education | Tulane University Fordham University |
Career
editO'Neill previously served as United States Consul-General in Chiang Mai.[5]
On July 9, 2025, President Donald Trump nominated O'Neill to be the next United States Ambassador to Thailand, succeeding Robert Godec.[6]
O'Neill was confirmed by the Senate on October 7, 2025.[7] He was among a group of over 100 nominees confirmed with a simple majority vote of 51 to 47.
Deputy Secretary of State Christopher Landau administered the oath of office to O'Neill on November 12, 2025 in the Franklin Room of the United States Department of State. He arrived in Bangkok in December 2025 and presented his credentials to King of Thailand Vajiralongkorn on February 11, 2026.
In his career, Mr. O’Neill has studied Thai, Chinese, Burmese, Bengali and Japanese.[3]
Personal life
editO'Neill is married to Sachiyo Kubo.[8]
References
edit- ↑ https://www.facebook.com/share/p/1AipYuMWXT/
- 1 2 Tangsathaporn, Poramet (July 11, 2025). "White House taps O'Neill as next envoy to Thailand". Bangkok Post. Retrieved July 11, 2025.
- 1 2 "Sean O'Neill". United States Department of State. Retrieved July 11, 2025.
- ↑ "On November 12, USABC President and CEO Ambassador Brian McFeeters joined the swearing-in ceremony of Ambassador Sean O'Neill, the new U.S. Ambassador to the Kingdom of Thailand. Ambassador… | US-ASEAN Business Council". www.linkedin.com. Retrieved November 14, 2025.
- ↑ "US rejects rumours of plans to store weapons at new Chiang Mai consulate". nationthailand. March 23, 2022. Retrieved July 11, 2025.
- ↑ "Nominations Sent to the Senate". The White House. July 9, 2025. Retrieved July 11, 2025.
- ↑ "Trump's nominee O'Neill confirmed as ambassador to Thailand". world.thaipbs.or.th. Retrieved October 8, 2025.
- ↑ "Signing of the Book of Condolences on the Passing of Her Majesty Queen Sirikit The Queen Mother". สถานเอกอัครราชทูต ณ กรุงวอชิงตัน (in Thai). Retrieved February 13, 2026.