diff --git a/reframe/frontend/cli.py b/reframe/frontend/cli.py
index af37b6ba3a..30c6a5ed18 100644
--- a/reframe/frontend/cli.py
+++ b/reframe/frontend/cli.py
@@ -999,6 +999,15 @@ def print_infoline(param, value):
             f'{len(testcases)} remaining'
         )
 
+        # Warn on any unset test variables for the final set of selected tests
+        for clsname in {type(tc.check).__name__ for tc in testcases}:
+            varlist = ', '.join(f'{v!r}' for v in loader.unset_vars(clsname))
+            if varlist:
+                printer.warning(
+                    f'test {clsname!r}: '
+                    f'the following variables were not set: {varlist}'
+                )
+
         # Filter in failed cases
         if options.failed:
             if options.restore_session is None:
diff --git a/reframe/frontend/loader.py b/reframe/frontend/loader.py
index 4e73bcc009..a286587345 100644
--- a/reframe/frontend/loader.py
+++ b/reframe/frontend/loader.py
@@ -60,9 +60,13 @@ def __init__(self, load_path, recurse=False, external_vars=None,
 
         # Variables set in the command line
         self._external_vars = external_vars or {}
+        self._unset_vars = {}
         self._skip_system_check = bool(skip_system_check)
         self._skip_prgenv_check = bool(skip_prgenv_check)
 
+    def unset_vars(self, testname):
+        return self._unset_vars.get(testname, [])
+
     def _module_name(self, filename):
         '''Figure out a module name from filename.
 
@@ -133,7 +137,7 @@ def _set_defaults(self, test_registry):
         if test_registry is None:
             return
 
-        unset_vars = {}
+        self._unset_vars = {}
         for test in test_registry:
             for name, val in self._external_vars.items():
                 if '.' in name:
@@ -149,16 +153,8 @@ def _set_defaults(self, test_registry):
                         val = fields.make_convertible(val)
 
                     if not test.setvar(varname, val):
-                        unset_vars.setdefault(test.__name__, [])
-                        unset_vars[test.__name__].append(varname)
-
-        # Warn for all unset variables
-        for testname, varlist in unset_vars.items():
-            varlist = ', '.join(f'{v!r}' for v in varlist)
-            getlogger().warning(
-                f'test {testname!r}: '
-                f'the following variables were not set: {varlist}'
-            )
+                        self._unset_vars.setdefault(test.__name__, [])
+                        self._unset_vars[test.__name__].append(varname)
 
     def load_from_module(self, module):
         '''Load user checks from module.