diff --git a/cmake/Modules/Packages/MDI.cmake b/cmake/Modules/Packages/MDI.cmake
index 447b941d99..b21e508b87 100644
--- a/cmake/Modules/Packages/MDI.cmake
+++ b/cmake/Modules/Packages/MDI.cmake
@@ -8,8 +8,8 @@ option(DOWNLOAD_MDI "Download and compile the MDI library instead of using an al
 
 if(DOWNLOAD_MDI)
   message(STATUS "MDI download requested - we will build our own")
-  set(MDI_URL "https://github.com/MolSSI-MDI/MDI_Library/archive/v1.4.16.tar.gz" CACHE STRING "URL for MDI tarball")
-  set(MDI_MD5 "407db44e2d79447ab5c1233af1965f65" CACHE STRING "MD5 checksum for MDI tarball")
+  set(MDI_URL "https://github.com/MolSSI-MDI/MDI_Library/archive/v1.4.26.tar.gz" CACHE STRING "URL for MDI tarball")
+  set(MDI_MD5 "3124bb85259471e2a53a891f04bf697a" CACHE STRING "MD5 checksum for MDI tarball")
   mark_as_advanced(MDI_URL)
   mark_as_advanced(MDI_MD5)
   GetFallbackURL(MDI_URL MDI_FALLBACK)
diff --git a/lib/mdi/Install.py b/lib/mdi/Install.py
index 316313ded8..c455f2d064 100644
--- a/lib/mdi/Install.py
+++ b/lib/mdi/Install.py
@@ -32,7 +32,7 @@ make lib-mdi args="-m mpi" # build MDI lib with same settings as in the mpi Make
 
 # settings
 
-version = "1.4.16"
+version = "1.4.26"
 url = "https://github.com/MolSSI-MDI/MDI_Library/archive/v%s.tar.gz" % version
 
 # known checksums for different MDI versions. used to validate the download.
@@ -41,6 +41,7 @@ checksums = { \
               '1.4.12' : '7a222353ae8e03961d5365e6cd48baee', \
               '1.4.14' : '7a059bb12535360fdcb7de8402f9a0fc', \
               '1.4.16' : '407db44e2d79447ab5c1233af1965f65', \
+              '1.4.26' : '3124bb85259471e2a53a891f04bf697a', \
               }
 
 # print error message or help