diff --git a/ci/x86_64-windows-debug.ps1 b/ci/x86_64-windows-debug.ps1
index 65828c093d573015a90150f0e84825b05cf365be..6cd28db466dda3b05d4195c33e36c8f0fadc6b4d 100644
--- a/ci/x86_64-windows-debug.ps1
+++ b/ci/x86_64-windows-debug.ps1
@@ -60,7 +60,7 @@ Write-Output "Main test suite..."
   -Dskip-non-native `
   -Dskip-release `
   -Denable-symlinks-windows `
-  --test-timeout 10m
+  --test-timeout 30m
 CheckLastExitCode
 
 Write-Output "Build x86_64-windows-msvc behavior tests using the C backend..."
diff --git a/ci/x86_64-windows-release.ps1 b/ci/x86_64-windows-release.ps1
index 246d9a993ca57b406654845e72f11629d29e09db..f3cdd66f48940f16c950c9551573c9ddb5b41bff 100644
--- a/ci/x86_64-windows-release.ps1
+++ b/ci/x86_64-windows-release.ps1
@@ -59,7 +59,7 @@ Write-Output "Main test suite..."
   -Dstatic-llvm `
   -Dskip-non-native `
   -Denable-symlinks-windows `
-  --test-timeout 10m
+  --test-timeout 30m
 CheckLastExitCode
 
 # Ensure that stage3 and stage4 are byte-for-byte identical.