Eastphalian, or Eastfalian (German: Ostfälisch, Eastphalian and Low Saxon: ostfälsch Platt), is a dialect of Low German, spoken in southeastern parts of Lower Saxony and western parts of Saxony-Anhalt in Germany.

Eastphalian as a separate dialect was determined by 19th century linguistics, tracing it back to Old Saxon variants spoken in eastern parts of the medieval stem duchy of Saxony.

Towards the Elbe region in the southeast, the language area is increasingly influenced by the High German consonant shift.

[3] Another striking difference between Eastphalian and all other Low German dialects is the absence (or undoing) of sound expansion in open syllable before -el, -en, -er in the following syllable, e. g. Eastphalian Löppel [ˈlœpl̩], betten [ˈbɛtn̩], Pepper [ˈpɛpɐ] ("spoon, bit, pepper") versus Northern Low Saxon Läpel [ˈlɛːpl̩], bäten [ˈbɛːtn̩], Päper [ˈpɛːpɐ].

These include for [ˈfɔr], unner [ˈʊnər] and over (Hildesheim) [ˈɛo̯vər], as opposed to Northern Lower Saxon för, ünner and över.