The district name was changed to Mueang Nakhon Nayok on 1 January 1939, to correspond with the name of the province.

The Nakhon Nayok River and Khlong Tha Dan are important water resources.

The district is divided into thirteen subdistricts (tambons), which are further subdivided into 125 villages mubans).

[1] As of December 2023 there are: two municipalities (thesaban), of which Nakhon Nayok itself has town status (thesaban mueang) and covers subdistrict Nakhon Nayok and parts of Tha Chang, Ban Yai, Wang Krachom and Phrommani subdistricts.

There are further twelve subdistrict administrative organizations - SAO (ongkan borihan suan tambon -o bo to)[1][2]