diff --git a/.buildkite/pipeline.yml b/.buildkite/pipeline.yml
index a0e3eef5476..10e070173db 100644
--- a/.buildkite/pipeline.yml
+++ b/.buildkite/pipeline.yml
@@ -4,7 +4,7 @@ steps:
     env:
       ZEPHYR_TOOLCHAIN_VARIANT: "zephyr"
       ZEPHYR_SDK_INSTALL_DIR: "/opt/sdk/zephyr-sdk-0.12.2"
-    parallelism: 40
+    parallelism: 20
     timeout_in_minutes: 180
     retry:
       manual: true