diff --git a/gematriapy/gematria.py b/gematriapy/gematria.py
index d484b6f..ab4e6d4 100644
--- a/gematriapy/gematria.py
+++ b/gematriapy/gematria.py
@@ -27,6 +27,16 @@
 ])
 
 
+HEBREW_ALL_LETTERS = {
+    **HEBREW_BASIC_LETTERS,
+    "ך": 20,
+    "ם": 40,
+    "ן": 50,
+    "ף": 80,
+    "ץ": 90,
+}
+
+
 def to_hebrew(number: int) -> str:
     """
     Convert number to Hebrew letter(s).
@@ -68,5 +78,5 @@ def to_number(hebrew: str) -> int:
     """
     sum = 0
     for letter in hebrew:
-        sum += HEBREW_BASIC_LETTERS.get(letter, 0)
+        sum += HEBREW_ALL_LETTERS.get(letter, 0)
     return sum
diff --git a/tests/test_to_number.py b/tests/test_to_number.py
index e889423..26de01a 100644
--- a/tests/test_to_number.py
+++ b/tests/test_to_number.py
@@ -15,6 +15,20 @@ def test_long_hebrew_v1(self):
     def test_long_hebrew_v2(self):
         self.assertEqual(gematriapy.to_number("רטו"), 215)
 
+    def test_long_hebrew_v3(self):
+        self.assertEqual(gematriapy.to_number("שלום"), 376)
+
+    def test_single_final_letter(self):
+        """
+        In Hebrew, 'final' letters are different from regular letters.
+        Some letters have a special shape if positioned at the end of a word.
+        """
+        self.assertEqual(gematriapy.to_number("ך"), 20)
+        self.assertEqual(gematriapy.to_number("ם"), 40)
+        self.assertEqual(gematriapy.to_number("ן"), 50)
+        self.assertEqual(gematriapy.to_number("ף"), 80)
+        self.assertEqual(gematriapy.to_number("ץ"), 90)
+
     def test_illegal_hebrew_number_v1(self):
         """
         In Hebrew, letters representing a numerical value should have an order: