Is Firmenfiliale der, die or das?

The correct German article for Firmenfiliale is die. The noun Firmenfiliale is Feminine. So you always say: die Firmenfiliale. Learn the article together with the noun — German nouns don't follow predictable gender rules most of the time.

The plural of Firmenfiliale is: die Firmenfilialen. In the plural, every German noun takes the article "die". So: die Firmenfilialen. Example: ein Firmenfiliale → zwei Firmenfilialen.

Correct: die Firmenfilialen. The form "die Firmenfiliales" is wrong. The plural of die Firmenfiliale is die Firmenfilialen. In the nominative plural, you always use the article "die".

die Firmenfiliale follows the four German cases. Nominative: die Firmenfiliale, Accusative: die Firmenfiliale, Dative: der Firmenfiliale, Genitive: der Firmenfiliale. In plural: die Firmenfilialen / den Firmenfilialen. Learn these forms together with the noun.

The genitive singular of die Firmenfiliale is: der Firmenfiliale. The genitive plural is der Firmenfilialen. German uses the genitive to express possession or belonging. Example: die Farbe der Firmenfiliale.

The dative plural of Firmenfiliale is: den Firmenfilialen. In German, dative plural nouns usually end in "-n". So you say: "mit den Firmenfilialen". Use this case after prepositions like mit, von, bei, zu.

Firmenfiliale ends in -e. German nouns with this ending are almost always feminine. Nouns ending in -e are often feminine (die), especially two-syllable words. That's why the article for Firmenfiliale is die.

Firmenfiliale is a noun and must be capitalized in German. You'll find example sentences above for each case. The article die stays the same in nominative singular but changes in other cases. Practice declension in your own sentences.

Yes, Firmenfiliale is a noun (also called a substantive). German nouns are always capitalized. The article for Firmenfiliale is die. Every German noun has a fixed article you must memorize.