diff --git a/perf/benchmark-subset.cc b/perf/benchmark-subset.cc
index 237dbe480..28ad93c6b 100644
--- a/perf/benchmark-subset.cc
+++ b/perf/benchmark-subset.cc
@@ -106,13 +106,9 @@ void AddGlyphs(unsigned num_glyphs_in_font,
 // the subsetting operations.
 static hb_face_t* preprocess_face(hb_face_t* face)
 {
-  #ifdef HB_EXPERIMENTAL_API
   hb_face_t* new_face = hb_subset_preprocess(face);
   hb_face_destroy(face);
   return new_face;
-  #else
-  return face;
-  #endif
 }
 
 /* benchmark for subsetting a font */
diff --git a/src/gen-def.py b/src/gen-def.py
index f6b98bfd2..857102d7c 100755
--- a/src/gen-def.py
+++ b/src/gen-def.py
@@ -22,7 +22,6 @@ if '--experimental-api' not in sys.argv:
 """hb_subset_repack_or_fail
 hb_subset_input_pin_axis_location
 hb_subset_input_pin_axis_to_default
-hb_subset_preprocess
 hb_subset_input_override_name_table
 """.splitlines ()
 	symbols = [x for x in symbols if x not in experimental_symbols]
diff --git a/src/hb-subset-input.cc b/src/hb-subset-input.cc
index 5165a7904..d210a8e79 100644
--- a/src/hb-subset-input.cc
+++ b/src/hb-subset-input.cc
@@ -448,16 +448,15 @@ hb_subset_input_pin_axis_location (hb_subset_input_t  *input,
 #endif
 #endif
 
-#ifdef HB_EXPERIMENTAL_API
 /**
  * hb_subset_preprocess
  * @input: a #hb_face_t object.
  *
  * Preprocesses the face and attaches data that will be needed by the
  * subsetter. Future subsetting operations can then use the precomputed data
- * to speed up the subsetting operation.
+ * to speed up the subsetting operation. Returns a new hb_face_t*.
  *
- * Since: EXPERIMENTAL
+ * Since: REPLACEME
  **/
 
 HB_EXTERN hb_face_t *
@@ -514,7 +513,6 @@ hb_subset_preprocess (hb_face_t *source)
 
   return new_source;
 }
-#endif
 
 #ifdef HB_EXPERIMENTAL_API
 /**
diff --git a/src/hb-subset.h b/src/hb-subset.h
index ac05ecd6f..ffffd6ad9 100644
--- a/src/hb-subset.h
+++ b/src/hb-subset.h
@@ -181,10 +181,6 @@ hb_subset_input_pin_axis_location (hb_subset_input_t  *input,
 #endif
 
 #ifdef HB_EXPERIMENTAL_API
-
-HB_EXTERN hb_face_t *
-hb_subset_preprocess (hb_face_t *source);
-
 HB_EXTERN hb_bool_t
 hb_subset_input_override_name_table (hb_subset_input_t  *input,
 				     hb_ot_name_id_t     name_id,
@@ -196,6 +192,9 @@ hb_subset_input_override_name_table (hb_subset_input_t  *input,
 
 #endif
 
+HB_EXTERN hb_face_t *
+hb_subset_preprocess (hb_face_t *source);
+
 HB_EXTERN hb_face_t *
 hb_subset_or_fail (hb_face_t *source, const hb_subset_input_t *input);
 
diff --git a/test/subset/run-tests.py b/test/subset/run-tests.py
index 6a2146dbe..db3c042a1 100755
--- a/test/subset/run-tests.py
+++ b/test/subset/run-tests.py
@@ -47,14 +47,16 @@ def fail_test (test, cli_args, message):
 	print ('  expected_file	    %s' % os.path.abspath (expected_file))
 	return 1
 
-def run_test (test, should_check_ots):
+def run_test (test, should_check_ots, preprocess):
 	out_file = os.path.join (tempfile.mkdtemp (), test.get_font_name () + '-subset' + test.get_font_extension ())
 	cli_args = ["--font-file=" + test.font_path,
 		    "--output-file=" + out_file,
 		    "--unicodes=%s" % test.unicodes (),
-		    "--preprocess-face",
 		    "--drop-tables+=DSIG",
 		    "--drop-tables-=sbix"]
+	if preprocess:
+		cli_args.extend(["--preprocess-face",])
+
 	cli_args.extend (test.get_profile_flags ())
 	if test.get_instance_flags ():
 		cli_args.extend (["--instance=%s" % ','.join(test.get_instance_flags ())])
@@ -142,7 +144,10 @@ for path in args:
 		print ("Running tests in " + path)
 		test_suite = SubsetTestSuite (path, f.read ())
 		for test in test_suite.tests ():
-			fails += run_test (test, has_ots)
+			# Tests are run with and without preprocessing, results should be the
+			# same between them.
+			fails += run_test (test, has_ots, False)
+			fails += run_test (test, has_ots, True)
 
 if fails != 0:
 	sys.exit ("%d test(s) failed." % fails)
diff --git a/util/hb-subset.cc b/util/hb-subset.cc
index 0c545ddc5..e02cff8d8 100644
--- a/util/hb-subset.cc
+++ b/util/hb-subset.cc
@@ -34,11 +34,7 @@
 
 static hb_face_t* preprocess_face(hb_face_t* face)
 {
-  #ifdef HB_EXPERIMENTAL_API
   return hb_subset_preprocess (face);
-  #else
-  return hb_face_reference(face);
-  #endif
 }
 
 /*