Context
Reminding someone that of course they're invited.
Huelga decir que estás invitado.
'It goes without saying' — huelga decir is the formal equivalent. Huelga = it strikes (as unnecessary).
Said before stating something obvious — paradoxically said even though it apparently goes without saying.
'Va sin decir' doesn't exist in Spanish. The equivalent is a completely different phrase.
Context
Reminding someone that of course they're invited.
Huelga decir que estás invitado.
'It goes without saying' — huelga decir is the formal equivalent. Huelga = it strikes (as unnecessary).
Context
Pointing out that of course quality costs more.
Ni que decir tiene que la calidad tiene un precio.
'It goes without saying that quality has a price' — ni que decir tiene is the most natural version.
Context
Before stating an obvious consequence.
Está claro que...
It's clear that... — simpler but widely used when something is assumed.
Context
Adding a caveat that's obviously understood.
Por supuesto, sin que haga falta decirlo...
Of course, without needing to say it... — verbose but correct.
Context
Reaffirming a given.
Es de cajón.
'It's in the drawer' — completely obvious, doesn't need to be said.