diff --git a/eng/pipelines/runtime-ioslike.yml b/eng/pipelines/runtime-ioslike.yml
index 1100ec500ce6ff..11477a3e175cba 100644
--- a/eng/pipelines/runtime-ioslike.yml
+++ b/eng/pipelines/runtime-ioslike.yml
@@ -4,6 +4,24 @@
 
 trigger: none
 
+# To reduce the load on the pipeline, enable it only for PRs that affect Mono LLVM related code.
+pr:
+  branches:
+    include:
+    - main
+    - release/*.*
+
+  paths:
+    include:
+      - src/mono/mono/mini/aot-*.*
+      - src/mono/mono/mini/llvm-*.*
+      - src/mono/mono/mini/mini-llvm-*.*
+      - src/mono/mono/mini/intrinsics.c
+      - src/mono/mono/mini/simd-*.*
+      - src/mono/mono/mini/decompose.c
+      - src/mono/mono/mini/method-to-ir.c
+      - src/mono/mono/mini/mini.c
+
 variables:
   - template: /eng/pipelines/common/variables.yml
 
diff --git a/eng/pipelines/runtime-llvm.yml b/eng/pipelines/runtime-llvm.yml
index 5be2a5b063aaaa..6f3d16767ddbb3 100644
--- a/eng/pipelines/runtime-llvm.yml
+++ b/eng/pipelines/runtime-llvm.yml
@@ -28,6 +28,24 @@ schedules:
       - main
     always: false # run only if there were changes since the last successful scheduled run.
 
+# To reduce the load on the pipeline, enable it only for PRs that affect Mono LLVM related code.
+pr:
+  branches:
+    include:
+    - main
+    - release/*.*
+
+  paths:
+    include:
+      - src/mono/mono/mini/aot-*.*
+      - src/mono/mono/mini/llvm-*.*
+      - src/mono/mono/mini/mini-llvm-*.*
+      - src/mono/mono/mini/intrinsics.c
+      - src/mono/mono/mini/simd-*.*
+      - src/mono/mono/mini/decompose.c
+      - src/mono/mono/mini/method-to-ir.c
+      - src/mono/mono/mini/mini.c
+
 variables:
   - template: /eng/pipelines/common/variables.yml