Can you prepare spells in higher level spell slots?

[Valanarch]

Could I prepare Lightning Bolt in a 4th level spell slot without using heighten spell?

[Hamste]

Yes, you can prepare spells in a higher slot even without heighten you just don't gain any benefit from it.

[HunterOfJello]

Yes. You can always do that.


Spell Slots (http://www.d20srd.org/srd/magicOverview/arcaneSpells.htm#wizardSpellSlots)

The various character class tables show how many spells of each level a character can cast per day. These openings for daily spells are called spell slots. A spellcaster always has the option to fill a higher-level spell slot with a lower-level spell. A spellcaster who lacks a high enough ability score to cast spells that would otherwise be his or her due still gets the slots but must fill them with spells of lower level.


Spell Slots (http://www.d20srd.org/srd/magicOverview/divineSpells.htm#divineSpellSlots)

The various character class tables show how many spells of each level a character can cast per day. These openings for daily spells are called spell slots. A spellcaster always has the option to fill a higher-level spell slot with a lower-level spell. A spellcaster who lacks a high enough ability score to cast spells that would otherwise be his or her due still gets the slots but must fill them with spells of lower level.

[Lord Vukodlak]

Yes, you can prepare spells in a higher slot even without heighten you just don't gain any benefit from it.

And spontaneous casters can also use higher level slots to cast lower level spells. This is an often forgotten tactical decision that can save lives.

[ryu]

Yep totally. Although there is almost ALWAYS a superior thing to do. Apply metamagic, find a spell of similar design at that level with a tastier effect, or even just pick a different type of effect on a higher magnitude. In most situations one of those is going to be both available and preferable.