diff --git a/cmake/CMakeLists.txt b/cmake/CMakeLists.txt
index 7fc2304a4c..35c0708d36 100644
--- a/cmake/CMakeLists.txt
+++ b/cmake/CMakeLists.txt
@@ -45,7 +45,7 @@ foreach(PKG ${PACKAGES})
   option(ENABLE_${PKG} "Build ${PKG} Package" OFF)
 endforeach()
 
-set(ACCEL_PACKAGES USER-OMP)
+set(ACCEL_PACKAGES USER_OMP)
 foreach(PKG ${ACCEL_PACKAGES})
   option(ENABLE_${PKG} "Build ${PKG} Package" OFF)
 endforeach()
@@ -139,7 +139,31 @@ endforeach()
 # packages which selectively include variants based on enabled styles
 # e.g. accelerator packages
 
-# TODO
+if(ENABLE_USER_OMP)
+    find_package(OpenMP REQUIRED)
+    if (OPENMP_FOUND)
+        set (CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${OpenMP_C_FLAGS}")
+        set (CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${OpenMP_CXX_FLAGS}")
+    else()
+        message(FATAL_ERROR "USER-OMP requires a compiler with OpenMP support")
+    endif()
+
+    set(USER_OMP_SOURCES_DIR ${LAMMPS_SOURCE_DIR}/USER-OMP)
+    set(USER_OMP_SOURCES ${USER_OMP_SOURCES_DIR}/thr_data.cpp
+                         ${USER_OMP_SOURCES_DIR}/thr_omp.cpp
+                         ${USER_OMP_SOURCES_DIR}/fix_nh_omp.cpp
+                         ${USER_OMP_SOURCES_DIR}/fix_nh_sphere_omp.cpp)
+    set_property(GLOBAL PROPERTY "OMP_SOURCES" "${USER_OMP_SOURCES}")
+
+    # detects styles which have USER-OMP version
+    RegisterStylesExt(${USER_OMP_SOURCES_DIR} omp OMP_SOURCES)
+
+    get_property(USER_OMP_SOURCES GLOBAL PROPERTY OMP_SOURCES)
+
+    list(APPEND LIB_SOURCES ${USER_OMP_SOURCES})
+    include_directories(${USER_OMP_SOURCES_DIR})
+endif()
+
 
 if(ENABLE_REAX)
   enable_language(Fortran)
diff --git a/cmake/Modules/StyleHeaderUtils.cmake b/cmake/Modules/StyleHeaderUtils.cmake
index 2ee9496671..55a6c15223 100644
--- a/cmake/Modules/StyleHeaderUtils.cmake
+++ b/cmake/Modules/StyleHeaderUtils.cmake
@@ -11,6 +11,33 @@ function(FindStyleHeaders path style_class file_pattern headers)
     set_property(GLOBAL PROPERTY ${headers} "${hlist}")
 endfunction(FindStyleHeaders)
 
+function(FindStyleHeadersExt path style_class extension headers sources)
+    get_property(hlist GLOBAL PROPERTY ${headers})
+    get_property(slist GLOBAL PROPERTY ${sources})
+    set(ext_list)
+    get_filename_component(abs_path "${path}" ABSOLUTE)
+
+    foreach(file_name ${hlist})
+        get_filename_component(basename ${file_name} NAME_WE)
+        set(ext_file_name "${abs_path}/${basename}_${extension}.h")
+        if(EXISTS "${ext_file_name}")
+            file(STRINGS ${ext_file_name} is_style LIMIT_COUNT 1 REGEX ${style_class})
+            if(is_style)
+                list(APPEND ext_list ${ext_file_name})
+
+                set(source_file_name "${abs_path}/${basename}_${extension}.cpp")
+                if(EXISTS "${source_file_name}")
+                    list(APPEND slist ${source_file_name})
+                endif()
+            endif()
+        endif()
+    endforeach()
+
+    list(APPEND hlist ${ext_list})
+    set_property(GLOBAL PROPERTY ${headers} "${hlist}")
+    set_property(GLOBAL PROPERTY ${sources} "${slist}")
+endfunction(FindStyleHeadersExt)
+
 function(CreateStyleHeader path filename)
     math(EXPR N "${ARGC}-2")
 
@@ -57,6 +84,29 @@ function(RegisterStyles search_path)
     FindStyleHeaders(${search_path} REGION_CLASS    region_    REGION    ) # region    ) # domain
 endfunction(RegisterStyles)
 
+function(RegisterStylesExt search_path extension sources)
+    FindStyleHeadersExt(${search_path} ANGLE_CLASS     ${extension}  ANGLE     ${sources})
+    FindStyleHeadersExt(${search_path} ATOM_CLASS      ${extension}  ATOM_VEC  ${sources})
+    FindStyleHeadersExt(${search_path} BODY_CLASS      ${extension}  BODY      ${sources})
+    FindStyleHeadersExt(${search_path} BOND_CLASS      ${extension}  BOND      ${sources})
+    FindStyleHeadersExt(${search_path} COMMAND_CLASS   ${extension}  COMMAND   ${sources})
+    FindStyleHeadersExt(${search_path} COMPUTE_CLASS   ${extension}  COMPUTE   ${sources})
+    FindStyleHeadersExt(${search_path} DIHEDRAL_CLASS  ${extension}  DIHEDRAL  ${sources})
+    FindStyleHeadersExt(${search_path} DUMP_CLASS      ${extension}  DUMP      ${sources})
+    FindStyleHeadersExt(${search_path} FIX_CLASS       ${extension}  FIX       ${sources})
+    FindStyleHeadersExt(${search_path} IMPROPER_CLASS  ${extension}  IMPROPER  ${sources})
+    FindStyleHeadersExt(${search_path} INTEGRATE_CLASS ${extension}  INTEGRATE ${sources})
+    FindStyleHeadersExt(${search_path} KSPACE_CLASS    ${extension}  KSPACE    ${sources})
+    FindStyleHeadersExt(${search_path} MINIMIZE_CLASS  ${extension}  MINIMIZE  ${sources})
+    FindStyleHeadersExt(${search_path} NBIN_CLASS      ${extension}  NBIN      ${sources})
+    FindStyleHeadersExt(${search_path} NPAIR_CLASS     ${extension}  NPAIR     ${sources})
+    FindStyleHeadersExt(${search_path} NSTENCIL_CLASS  ${extension}  NSTENCIL  ${sources})
+    FindStyleHeadersExt(${search_path} NTOPO_CLASS     ${extension}  NTOPO     ${sources})
+    FindStyleHeadersExt(${search_path} PAIR_CLASS      ${extension}  PAIR      ${sources})
+    FindStyleHeadersExt(${search_path} READER_CLASS    ${extension}  READER    ${sources})
+    FindStyleHeadersExt(${search_path} REGION_CLASS    ${extension}  REGION    ${sources})
+endfunction(RegisterStylesExt)
+
 function(GenerateStyleHeaders output_path)
     GenerateStyleHeader(${output_path} ANGLE      angle     ) # force
     GenerateStyleHeader(${output_path} ATOM_VEC   atom      ) # atom      atom_vec_hybrid