diff --git a/tests/CMakeLists.txt b/tests/CMakeLists.txt
index 0892ee34c7a..d6825fabd70 100644
--- a/tests/CMakeLists.txt
+++ b/tests/CMakeLists.txt
@@ -15,9 +15,13 @@ if (USE_MPI)
   else ()
     set(num_ranks ${TEST_MPI_RANKS})
   endif ()
+  math(EXPR test_processors "${num_ranks} * ${NUM_THREADS}")
+
   message(
     "Tests will run with ${num_ranks} MPI ranks and ${NUM_THREADS} OpenMP threads each"
   )
+else ()
+  set(test_processors ${NUM_THREADS})
 endif ()
 
 # =================================== DBCSR PERF TESTS
@@ -53,7 +57,10 @@ foreach (dbcsr_perf_test ${DBCSR_PERF_TESTS})
                      "${CMAKE_CURRENT_SOURCE_DIR}/${dbcsr_perf_test}")
   endif ()
   set_tests_properties(dbcsr_perf:${dbcsr_perf_test}
-                       PROPERTIES ENVIRONMENT OMP_NUM_THREADS=${NUM_THREADS})
+    PROPERTIES
+    ENVIRONMENT OMP_NUM_THREADS=${NUM_THREADS}
+    PROCESSORS ${test_processors}
+  )
 endforeach ()
 
 # =================================== DBCSR CORRECTNESS TESTS Define all the
@@ -131,9 +138,12 @@ foreach (dbcsr_test ${DBCSR_TESTS_FTN})
   endif ()
   if (OpenMP_FOUND)
     target_link_libraries(${dbcsr_test} OpenMP::OpenMP_Fortran)
-    set_tests_properties(${dbcsr_test}
-                         PROPERTIES ENVIRONMENT OMP_NUM_THREADS=${NUM_THREADS})
   endif ()
+  set_tests_properties(${dbcsr_test}
+    PROPERTIES
+    ENVIRONMENT OMP_NUM_THREADS=${NUM_THREADS}
+    PROCESSORS ${test_processors}
+  )
 endforeach ()
 
 # set the __SHORT_FILE__ per file for dbcsr sources
@@ -161,11 +171,11 @@ if (WITH_C_API)
     else ()
       add_test(NAME ${dbcsr_test_cpp_name} COMMAND ./${dbcsr_test_cpp_name})
     endif ()
-    if (OpenMP_FOUND)
-      set_tests_properties(
-        ${dbcsr_test_cpp_name} PROPERTIES ENVIRONMENT
-                                          OMP_NUM_THREADS=${NUM_THREADS})
-    endif ()
+    set_tests_properties(${dbcsr_test_cpp_name}
+      PROPERTIES
+      ENVIRONMENT OMP_NUM_THREADS=${NUM_THREADS}
+      PROCESSORS ${test_processors}
+    )
   endforeach ()
 endif ()
 
@@ -178,11 +188,11 @@ if (NOT USE_MPI)
     target_link_libraries(${dbcsr_test_backend} PRIVATE dbcsr)
     # register unittest executable with CMake
     add_test(NAME ${dbcsr_test_backend} COMMAND ./${dbcsr_test_backend})
-    if (OpenMP_FOUND)
-      set_tests_properties(
-        ${dbcsr_test_backend} PROPERTIES ENVIRONMENT
-                                         OMP_NUM_THREADS=${NUM_THREADS})
-    endif ()
+    set_tests_properties(${dbcsr_test_backend}
+      PROPERTIES
+      ENVIRONMENT OMP_NUM_THREADS=${NUM_THREADS}
+      PROCESSORS ${NUM_THREADS}
+    )
   endforeach ()
 endif ()