 Of the Swiss national languages (), 4,067 speak German, 9 people speak French, 51 people speak Italian, and 11 people speak Romansh.The age distribution, , in Sennwald is; 565 children or 12.6% of the population are between 0 and 9 years old and 662 teenagers or 14.8% are between 10 and 19.Of the adult population, 540 people or 12.0% of the population are between 20 and 29 years old.