| Stac Rhos | |
| Elevation M: | 630 |
| Prominence M: | 25 |
| Listing: | sub Hewitt, Nuttall |
| Language: | Welsh |
| Location: | Gwynedd, Wales |
| Range: | Berwyn range |
| Grid Ref Uk: | SH 96914 27933 |
| Topo: | OS Landranger 125 |
Stac Rhos is a top of Pen y Boncyn Trefeilw in north east Wales. It forms a part of the Berwyn range called the Hirnantau.
The views from the summit are extensive, if unremarkable due to the featureless, flat moorland surroundings. The summit is marked by a small cairn, and a boundary stone. To the east is Cyrniau Nod, while Cefn Gwyntog is to the south-east.[1]