Effective from 1 January 2011, Filzbach is part of the municipality of Glarus Nord.

Of the rest of the land, 4.6% is settled (buildings or roads) and the remainder (19.1%) is non-productive (rivers, glaciers or mountains).

[2] The municipality is located on a terrace of the Kerenzerberg mountain above the Walensee.

Most of the population (as of 2000[update]) speaks German (92.6%), with Portuguese being second most common ( 1.3%) and Serbo-Croatian being third ( 1.3%).

[2] In the 2007 federal election the most popular party was the SVP which received 50.9% of the vote.