diff --git a/module/applications/advancement/item-choice-flow.mjs b/module/applications/advancement/item-choice-flow.mjs
index 8f623cc255..0bb0113c0a 100644
--- a/module/applications/advancement/item-choice-flow.mjs
+++ b/module/applications/advancement/item-choice-flow.mjs
@@ -1,3 +1,4 @@
+import Actor5e from "../../documents/actor/actor.mjs";
 import ItemGrantFlow from "./item-grant-flow.mjs";
 
 /**
@@ -169,12 +170,27 @@ export default class ItemChoiceFlow extends ItemGrantFlow {
    * @returns {number}
    */
   _maxSpellSlotLevel() {
-    const largestSlot = Object.entries(this.advancement.actor.system.spells).reduce((slot, [key, data]) => {
+    const spellcasting = this.advancement.item.spellcasting;
+    let spells;
+
+    // For advancements on classes or subclasses, use the largest slot available for that class
+    if ( spellcasting ) {
+      const progression = { slot: 0, pact: {} };
+      const maxSpellLevel = CONFIG.DND5E.SPELL_SLOT_TABLE[CONFIG.DND5E.SPELL_SLOT_TABLE.length - 1].length;
+      spells = Object.fromEntries(Array.fromRange(maxSpellLevel, 1).map(l => [`spell${l}`, {}]));
+      Actor5e.computeClassProgression(progression, this.advancement.item, { spellcasting });
+      Actor5e.prepareSpellcastingSlots(spells, spellcasting.type, progression);
+    }
+
+    // For all other items, use the largest slot possible
+    else spells = this.advancement.actor.system.spells;
+
+    const largestSlot = Object.entries(spells).reduce((slot, [key, data]) => {
       if ( data.max === 0 ) return slot;
       const level = parseInt(key.replace("spell", ""));
       if ( !Number.isNaN(level) && level > slot ) return level;
       return slot;
     }, -1);
-    return Math.max(this.advancement.actor.system.spells.pact.level, largestSlot);
+    return Math.max(spells.pact?.level ?? 0, largestSlot);
   }
 }
diff --git a/module/documents/actor/actor.mjs b/module/documents/actor/actor.mjs
index fb7af39b6f..d179cb389a 100644
--- a/module/documents/actor/actor.mjs
+++ b/module/documents/actor/actor.mjs
@@ -659,7 +659,7 @@ export default class Actor5e extends Actor {
    * @protected
    */
   _prepareSpellcasting() {
-    if ( this.type === "vehicle" ) return;
+    if ( !this.system.spells ) return;
 
     // Spellcasting DC
     const spellcastingAbility = this.system.abilities[this.system.attributes.spellcasting];
@@ -691,7 +691,7 @@ export default class Actor5e extends Actor {
       );
     }
 
-    for ( const type of Object.keys(types) ) {
+    for ( const type of Object.keys(CONFIG.DND5E.spellcastingTypes) ) {
       this.constructor.prepareSpellcastingSlots(this.system.spells, type, progression, { actor: this });
     }
   }