diff --git a/spacy/tests/tokenizer/test_tokenizer.py b/spacy/tests/tokenizer/test_tokenizer.py
index 82032b2da..4f5eddb95 100644
--- a/spacy/tests/tokenizer/test_tokenizer.py
+++ b/spacy/tests/tokenizer/test_tokenizer.py
@@ -180,3 +180,9 @@ def test_tokenizer_special_cases_idx(tokenizer):
     doc = tokenizer(text)
     assert doc[1].idx == 4
     assert doc[2].idx == 7
+
+
+def test_tokenizer_special_cases_spaces(tokenizer):
+    assert [t.text for t in tokenizer("a b c")] == ["a", "b", "c"]
+    tokenizer.add_special_case("a b c", [{"ORTH": "a b c"}])
+    assert [t.text for t in tokenizer("a b c")] == ["a b c"]
diff --git a/spacy/tokenizer.pyx b/spacy/tokenizer.pyx
index e22e0094b..d54c3521d 100644
--- a/spacy/tokenizer.pyx
+++ b/spacy/tokenizer.pyx
@@ -611,7 +611,7 @@ cdef class Tokenizer:
             self.mem.free(stale_special)
         self._rules[string] = substrings
         self._flush_cache()
-        if self.find_prefix(string) or self.find_infix(string) or self.find_suffix(string):
+        if self.find_prefix(string) or self.find_infix(string) or self.find_suffix(string) or " " in string:
             self._special_matcher.add(string, None, self._tokenize_affixes(string, False))
 
     def _reload_special_cases(self):