It is spoken in the watersheds of the Bača and lower Idrijca rivers, as well as the reaches of the Soča River in that area, bounded on the west by a line west of Tolmin and Most na Soči.
Other settlements in the dialect area include Grahovo ob Bači.
[3][4] The Tolmin dialect lacks pitch accent, except in Čiginj, where this is partially retained.
It has short vowels resulting from accentual retraction of the type nàga < nogà 'foot', vowel reduction as in the central Slovene dialects, b < v (known as betacizem in Slovene), and innovative Slovenian palatalization (e.g., ščìra < sekira 'axe').
The dialect has undergone complete akanye and the lenition of g > [ɦ].