diff --git a/nightly-main/windows/1809/Dockerfile b/nightly-main/windows/1809/Dockerfile
index 5ef600bf..5a3bfc65 100644
--- a/nightly-main/windows/1809/Dockerfile
+++ b/nightly-main/windows/1809/Dockerfile
@@ -128,8 +128,10 @@ RUN Write-Host -NoNewLine ('Downloading {0} ... ' -f ${env:VSB});
 
 # Install Swift toolchain.
 ARG SWIFT_RELEASE_METADATA=https://download.swift.org/development/windows10/latest-build.json
+# Pinned to 3/10 snapshot due to https://github.com/swiftlang/swift/issues/80356
+# $SWIFT_URL = "\"https://download.swift.org/development/windows10/$($Release.dir)/$($Release.download)\""; \
 RUN $Release = curl.exe -sL ${env:SWIFT_RELEASE_METADATA} | ConvertFrom-JSON;   \
-    $SWIFT_URL = "\"https://download.swift.org/development/windows10/$($Release.dir)/$($Release.download)\""; \
+    $SWIFT_URL = "\"https://download.swift.org/development/windows10/swift-DEVELOPMENT-SNAPSHOT-2025-03-10-a/swift-DEVELOPMENT-SNAPSHOT-2025-03-10-a-windows10.exe\""; \
     Write-Host -NoNewLine ('Downloading {0} ... ' -f ${SWIFT_URL});             \
     Invoke-WebRequest -Uri ${SWIFT_URL} -OutFile installer.exe;                 \
     Write-Host '✓';                                                             \
diff --git a/nightly-main/windows/LTSC2022/Dockerfile b/nightly-main/windows/LTSC2022/Dockerfile
index b1af4a39..65a210dc 100644
--- a/nightly-main/windows/LTSC2022/Dockerfile
+++ b/nightly-main/windows/LTSC2022/Dockerfile
@@ -128,8 +128,10 @@ RUN Write-Host -NoNewLine ('Downloading {0} ... ' -f ${env:VSB});
 
 # Install Swift toolchain.
 ARG SWIFT_RELEASE_METADATA=https://download.swift.org/development/windows10/latest-build.json
+# Pinned to 3/10 snapshot due to https://github.com/swiftlang/swift/issues/80356
+# $SWIFT_URL = "\"https://download.swift.org/development/windows10/$($Release.dir)/$($Release.download)\""; \
 RUN $Release = curl.exe -sL ${env:SWIFT_RELEASE_METADATA} | ConvertFrom-JSON;   \
-    $SWIFT_URL = "\"https://download.swift.org/development/windows10/$($Release.dir)/$($Release.download)\""; \
+    $SWIFT_URL = "\"https://download.swift.org/development/windows10/swift-DEVELOPMENT-SNAPSHOT-2025-03-10-a/swift-DEVELOPMENT-SNAPSHOT-2025-03-10-a-windows10.exe\""; \
     Write-Host -NoNewLine ('Downloading {0} ... ' -f ${SWIFT_URL});             \
     Invoke-WebRequest -Uri ${SWIFT_URL} -OutFile installer.exe;                 \
     Write-Host '✓';                                                             \