Which spell save DC do you use when casting with warlock slots?

Question

So I have found a few questions that are closely related, but I can't find exactly the answer I am looking for. Say you are multiclassed warlock and wizard. You can cast either class's spells through any of the spell slots. But which stat is used for the spell DCs? If you cast a warlock spell with a wizard spell slot, should the DC be calculated with Int or Cha? (or vice versa, if you cast a wizard spell with a warlock spell slot)

Essentially, is the ability used to calculate DC based on the class that the spell is originally from, or the slot it is being cast with?

Related: Can a multiclass character use either of its spellcasting modifiers for spells?, Multiclass Warlock/Wizard: Can I use Int as spellcasting ability for Pact Magic slots?, If you are a multiclass spellcaster, does your save DC vary based on which class you got a spell from? — MikeQ, Mar 29 '20 at 01:20
@MikeQ I knew it had to be on here somewhere I just couldn't find it in a search. Thanks! — Tenuit, Mar 29 '20 at 01:22

score 0 · Answer 1 · edited Mar 29 '20 at 06:34

Depends on the source of the spell

The calculation for spell save DC is dependent on where the spell comes from.

If you know the spell from the wizard spell list, it would be 8 + proficiency bonus + Intelligence modifier.

However, if you know the spell from the warlock spell list, the spell save DC would be 8 + proficiency bonus + Charisma modifier.

TLDR: The spell save DC is dependent on which class you know the spell from.

Which spell save DC do you use when casting with warlock slots?

1 Answers1

Depends on the source of the spell