De or het postgirorekening?

The correct Dutch article is:

de postgirorekening

Rule Words ending in -ing: almost always de. See the rule

How to use postgirorekening

the postgirorekeningde postgirorekening
this postgirorekeningdeze postgirorekening
that postgirorekeningdie postgirorekening
our postgirorekeningonze postgirorekening
your postgirorekeningjouw postgirorekening
every postgirorekeningelke postgirorekening
which postgirorekening?welke postgirorekening?
a big postgirorekening / the big postgirorekeningeen grote postgirorekening, de grote postgirorekening