[4] Seah joined Temasek International, where he as Senior Managing Director, Special Projects (1 March - 30 September 2013) established a new entity to focus on natural gas investments.

[8][9] Seah was appointed as the Chairman of the NUS High School of Math and Science's Board of Governors in October 2021.

Seah has been credited by former Singapore Transport Minister Khaw Boon Wan for the train operator's performance.

[13] In 2020, he was conferred the Medal of Commendation (Gold) by National Trades Union Congress on May Day for his significant contributions to continuing workers' welfare and work prospects.

[15] Seah is a member of Eta Kappa Nu – an international honour society of the Institute of Electrical and Electronics Engineers.

Seah is a member of Ministry of Finance's ICT Projects Advisory Panel[16] and Honorary President of Singapore Table Tennis Association.