diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 9a316a869..473c03275 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -7,7 +7,7 @@ on:
     branches: [ master ]
 
 env:
-  LLVM_RELEASE_VERSION: 16
+  LLVM_RELEASE_VERSION: 18
 
 jobs:
 
@@ -446,7 +446,7 @@ jobs:
       fail-fast: false
       matrix:
         build_type: [Release, Debug]
-        llvm_version: [15, 16, 17]
+        llvm_version: [15, 16, 17, 18]
     steps:
       - uses: actions/checkout@v4
       - name: Download LLVM
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 0cc210c95..7acfe96be 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -98,15 +98,15 @@ endif()
 
 if(CMAKE_C_COMPILER_ID STREQUAL "MSVC")
     if (C3_LLVM_VERSION STREQUAL "auto")
-        set(C3_LLVM_VERSION "16")
+        set(C3_LLVM_VERSION "18")
     endif()
     FetchContent_Declare(
             LLVM_Windows
-            URL https://github.com/c3lang/win-llvm/releases/download/llvm_16_0_2/llvm-16.0.2-windows-amd64-msvc17-libcmt.7z
+            URL https://github.com/c3lang/win-llvm/releases/download/llvm_18_1_8/llvm-18.1.8-windows-amd64-msvc17-libcmt.7z
     )
     FetchContent_Declare(
             LLVM_Windows_debug
-            URL https://github.com/c3lang/win-llvm/releases/download/llvm_16_0_2/llvm-16.0.2-windows-amd64-msvc17-libcmt-dbg.7z
+            URL https://github.com/c3lang/win-llvm/releases/download/llvm_18_1_8/llvm-18.1.8-windows-amd64-msvc17-libcmt-dbg.7z
     )
     if(CMAKE_BUILD_TYPE STREQUAL "Debug")
         message("Loading Windows LLVM debug libraries, this may take a while...")