diff --git a/.changeset/fix-transition-duration-zero-jitter.md b/.changeset/fix-transition-duration-zero-jitter.md
new file mode 100644
index 000000000..056d01d38
--- /dev/null
+++ b/.changeset/fix-transition-duration-zero-jitter.md
@@ -0,0 +1,5 @@
+---
+"@stackflow/core": patch
+---
+
+Fix intermittent incorrect transition state when `transitionDuration` is set to 0 by ensuring `now >= eventDate` in the initial aggregate call within `dispatchEvent`.
diff --git a/core/src/makeCoreStore.ts b/core/src/makeCoreStore.ts
index 0043055c5..297ac948c 100644
--- a/core/src/makeCoreStore.ts
+++ b/core/src/makeCoreStore.ts
@@ -92,9 +92,10 @@ export function makeCoreStore(options: MakeCoreStoreOptions): CoreStore {
     },
     dispatchEvent(name, params) {
       const newEvent = makeEvent(name, params);
+
       const nextStackValue = aggregate(
         [...events.value, newEvent],
-        new Date().getTime(),
+        Math.max(newEvent.eventDate, new Date().getTime()),
       );
 
       events.value.push(newEvent);