diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index be7778c72..034c88124 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -331,7 +331,7 @@ jobs:
             setenvs: export LLVM_VERSION=10.0.0
                             OPENIMAGEIO_CMAKE_FLAGS="-DBUILD_FMT_VERSION=7.0.1"
                             PUGIXML_VERSION=v1.10
-          - desc: latest releases gcc11/C++17 llvm13 boost1.71 exr3.1 py3.9 avx2 batch-b16avx512
+          - desc: latest releases gcc11/C++17 llvm15 boost1.71 exr3.1 py3.9 avx2 batch-b16avx512
             nametag: linux-latest-releases
             os: ubuntu-22.04
             cxx_compiler: g++-11
@@ -347,7 +347,7 @@ jobs:
                             LLVM_DISTRO_NAME=ubuntu-18.04
                             OPENCOLORIO_VERSION=v2.2.0
                             PUGIXML_VERSION=v1.13
-          - desc: bleeding edge gcc12/C++17 llvm14 oiio/ocio/exr/pybind-master boost1.71 py3.10 avx2 batch-b16avx512
+          - desc: bleeding edge gcc12/C++17 llvm16 oiio/ocio/exr/pybind-master boost1.71 py3.10 avx2 batch-b16avx512
             nametag: linux-bleeding-edge
             os: ubuntu-22.04
             cxx_compiler: g++-12
diff --git a/src/cmake/externalpackages.cmake b/src/cmake/externalpackages.cmake
index 4e35ce877..61ce8c10a 100644
--- a/src/cmake/externalpackages.cmake
+++ b/src/cmake/externalpackages.cmake
@@ -147,9 +147,6 @@ if (LLVM_VERSION VERSION_GREATER_EQUAL 15.0
          "If you are using LLVM 15 or higher, you should also use clang version "
          "15 or higher, or you may get build errors.${ColorReset}\n")
 endif ()
-if (LLVM_VERSION VERSION_GREATER_EQUAL 18.0)
-    message (ERROR "${ColorYellow}OSL is not yet compatible with LLVM 18.${ColorReset}\n")
-endif ()
 if (LLVM_VERSION VERSION_GREATER_EQUAL 16.0)
     if (CMAKE_CXX_STANDARD VERSION_LESS 17)
         message (WARNING "${ColorYellow}LLVM 16+ requires C++17 or higher. "