Thap Krit Tai (Thai: ทับกฤชใต้) is a tambon (subdistrict) in Chum Saeng district, Nakhon Sawan province, Thailand.

[1] Thap Krit Tai is a northern part of Nakhon Sawan province.

Nan river and Bueng Thap Krit Tai are important sources of water.

The emblem of SAO Thap Krit Tai features paddy field and freshwater lake with mountains in the background inside the ears of rice frame.

[1] Thap Krit Tai is served by the Thap Krit and Khlong Pla Kot railway stations of the State Railway of Thailand (SRT), whose northern line runs through the area.