Raising the save for a spell

[blue_the_wolf]

can you make a spell harder to resist by putting it in a higher spell slot?

for example suppose a level 15 caster wants to cast a harder to resist charm person.

can they put it in the slot of a 7th level spell to raise the DC? by 6 or 7 points?

[Chemlak]

Not without using the Heighten Spell feat.

[Sentath]

Almost easier to raise the casting stat by that point.

[blue_the_wolf]

Heighten spell

great thanks.

looking to cast sanctuary with a high DC so that i can wander around supporting the team with less chance of being attacked.