diff --git a/alembic/script/revision.py b/alembic/script/revision.py
index 587e9049..5825da34 100644
--- a/alembic/script/revision.py
+++ b/alembic/script/revision.py
@@ -45,7 +45,7 @@
 _TR = TypeVar("_TR", bound=Optional[_RevisionOrStr])
 
 _relative_destination = re.compile(r"(?:(.+?)@)?(\w+)?((?:\+|-)\d+)")
-_revision_illegal_chars = ["@", "-", "+"]
+_revision_illegal_chars = ["@", "-", "+", ":"]
 
 
 class _CollectRevisionsProtocol(Protocol):
diff --git a/docs/build/unreleased/1540.rst b/docs/build/unreleased/1540.rst
new file mode 100644
index 00000000..3c42fe77
--- /dev/null
+++ b/docs/build/unreleased/1540.rst
@@ -0,0 +1,7 @@
+.. change::
+    :tags: usecase, revision
+    :tickets: 1540
+
+    Disallow ':' character in custom revision identifiers. Previously, using a colon in
+    a revision ID (e.g., 'REV:1') caused alembic to interpret it as a revision range,
+    resulting in upgrade failures.
\ No newline at end of file
diff --git a/tests/test_script_production.py b/tests/test_script_production.py
index 00150468..853767dc 100644
--- a/tests/test_script_production.py
+++ b/tests/test_script_production.py
@@ -393,6 +393,16 @@ def test_illegal_revision_chars(self):
             rev_id="no@atsigns",
         )
 
+        assert_raises_message(
+            util.CommandError,
+            r"Character\(s\) ':' not allowed in "
+            "revision identifier 'no:colons'",
+            command.revision,
+            self.cfg,
+            message="some message",
+            rev_id="no:colons",
+        )
+
         assert_raises_message(
             util.CommandError,
             r"Character\(s\) '-, @' not allowed in revision "