diff --git a/.vpython b/.vpython
index d0ca325f4..8b8a536ba 100644
--- a/.vpython
+++ b/.vpython
@@ -1,5 +1,20 @@
 python_version: "2.7"
 
+# The default set of platforms vpython checks for does not yet include mac-arm64.
+# Setting `verify_pep425_tag` to the list of platforms we explicitly must support
+# allows us to ensure that vpython specs stay mac-arm64-friendly
+verify_pep425_tag: [
+    {python: "cp27", abi: "cp27mu", platform: "manylinux1_x86_64"},
+    {python: "cp27", abi: "cp27mu", platform: "linux_arm64"},
+    {python: "cp27", abi: "cp27mu", platform: "linux_armv6l"},
+
+    {python: "cp27", abi: "cp27m", platform: "macosx_10_10_intel"},
+    {python: "cp27", abi: "cp27m", platform: "macosx_11_0_arm64"},
+
+    {python: "cp27", abi: "cp27m", platform: "win32"},
+    {python: "cp27", abi: "cp27m", platform: "win_amd64"}
+]
+
 # Used by:
 #   auth.py
 #   gerrit_util.py
diff --git a/.vpython3 b/.vpython3
index 3ab3f07d4..0d8bd39b5 100644
--- a/.vpython3
+++ b/.vpython3
@@ -1,5 +1,20 @@
 python_version: "3.8"
 
+# The default set of platforms vpython checks for does not yet include mac-arm64.
+# Setting `verify_pep425_tag` to the list of platforms we explicitly must support
+# allows us to ensure that vpython specs stay mac-arm64-friendly
+verify_pep425_tag: [
+    {python: "cp38", abi: "cp38", platform: "manylinux1_x86_64"},
+    {python: "cp38", abi: "cp38", platform: "linux_arm64"},
+    {python: "cp38", abi: "cp38", platform: "linux_armv6l"},
+
+    {python: "cp38", abi: "cp38", platform: "macosx_10_10_intel"},
+    {python: "cp38", abi: "cp38", platform: "macosx_11_0_arm64"},
+
+    {python: "cp38", abi: "cp38", platform: "win32"},
+    {python: "cp38", abi: "cp38", platform: "win_amd64"}
+]
+
 # Used by:
 #   auth.py
 #   gerrit_util.py