Kato Kastritsi () is a village and a community in the municipal unit of Rio, Achaea, Greece. The community consists of the villages Kato Kastritsi and Magoula. It is situated at about 100 m elevation in the northwestern foothills of the Panachaiko, 2 km southeast of Rio town centre, and adjacent to the campus of the University of Patras. Ano Kastritsi is 4 km to the southeast.
Historical population
{| class="wikitable"
! Year !! Population village !!Population community
|-
| 1981 || - || 518
|-
| 1991 || 380 || 677
|-
| 2001 || 514 || 712
|-
| 2011 || 758 || 1,046
|-
| 2021 || 545 || 798
|}
See also
- List of settlements in Achaea