An vs auf in German: when to use which

I see students struggle with the German prepositions ‘an’ and ‘auf’ during my lessons. Both describe locations and require either the Accusative or the Dative case. If we can ask ‘wohin’ (where to), then the preposition requires the Accusative, and if we ask ‘wo’ (where), then the Dative is needed. This raises the question of why we use cases after prepositions. The answer is simple: English uses two different prepositions to describe these two different scenarios, whereas German uses the same preposition but two separate cases to describe the same two scenarios.

on = auf + Dative and onto = auf + Accusative.

When do you use auf, and when do you use an? Auf is always used when something is resting on something else that is horizontal, and an is used when something is resting on something vertical: auf dem Tisch – on the table (horizontal) but an der Wand – on the wall (vertical).

Am is simply an + dem, used with masculine and neuter nouns in the dative: Das Bild hängt am Schrank. German also uses am for days and dates: am Montag, am 3. Oktober.

Please read on if you would like to learn about another set of prepositions: ‘zu’ + ‘nach’

Are you struggling to learn German?

An and auf stick faster in conversation than in a table. Regular practice with a German tutor in London or in German lessons online makes the choice automatic.