diff --git a/.changeset/spicy-ways-yawn.md b/.changeset/spicy-ways-yawn.md
new file mode 100644
index 0000000000..c18413247c
--- /dev/null
+++ b/.changeset/spicy-ways-yawn.md
@@ -0,0 +1,6 @@
+---
+'@firebase/ai': minor
+'firebase': minor
+---
+
+Update default hybrid-in-cloud model to `gemini-2.5-flash-lite`.
diff --git a/packages/ai/src/constants.ts b/packages/ai/src/constants.ts
index 0a6f7e9143..82ea4c7a9f 100644
--- a/packages/ai/src/constants.ts
+++ b/packages/ai/src/constants.ts
@@ -37,4 +37,4 @@ export const DEFAULT_FETCH_TIMEOUT_MS = 180 * 1000;
 /**
  * Defines the name of the default in-cloud model to use for hybrid inference.
  */
-export const DEFAULT_HYBRID_IN_CLOUD_MODEL = 'gemini-2.0-flash-lite';
+export const DEFAULT_HYBRID_IN_CLOUD_MODEL = 'gemini-2.5-flash-lite';