diff --git a/external/external_build.cmake b/external/external_build.cmake
index 0509be2..5942efb 100644
--- a/external/external_build.cmake
+++ b/external/external_build.cmake
@@ -41,7 +41,7 @@ IF(INTERNAL_NETCDF)
 ENDIF(INTERNAL_NETCDF)
 
 IF(INTERNAL_BOOST)
-  SET(BOOST_URL "https://boostorg.jfrog.io/artifactory/main/release/1.74.0/source/boost_1_74_0.tar.bz2" CACHE STRING "URL to download Boost from")
+  SET(BOOST_URL "https://boostorg.jfrog.io/artifactory/main/release/1.81.0/source/boost_1_81_0.tar.bz2" CACHE STRING "URL to download Boost from")
   mark_as_advanced(BOOST_URL)
 ELSE(INTERNAL_BOOST)
   find_package(Boost 1.74.0 COMPONENTS format spirit phoenix python FATAL_ERROR)