diff --git a/Misc/NEWS.d/next/Core and Builtins/2024-04-11-21-17-23.gh-issue-117431.ZxdAFN.rst b/Misc/NEWS.d/next/Core and Builtins/2024-04-11-21-17-23.gh-issue-117431.ZxdAFN.rst
new file mode 100644
index 00000000000000..1e77d5ba1413b8
--- /dev/null
+++ b/Misc/NEWS.d/next/Core and Builtins/2024-04-11-21-17-23.gh-issue-117431.ZxdAFN.rst	
@@ -0,0 +1 @@
+Improve performance of :meth:`str.startswith`, :meth:`str.endswith`, :meth:`str.removeprefix` and :meth:`str.removesuffix`.
diff --git a/Objects/unicodeobject.c b/Objects/unicodeobject.c
index 057b417074ebea..0d9fdc443cd315 100644
--- a/Objects/unicodeobject.c
+++ b/Objects/unicodeobject.c
@@ -9254,7 +9254,8 @@ tailmatch(PyObject *self,
     Py_ssize_t end_sub;
 
     ADJUST_INDICES(start, end, PyUnicode_GET_LENGTH(self));
-    end -= PyUnicode_GET_LENGTH(substring);
+    Py_ssize_t substring_length = PyUnicode_GET_LENGTH(substring);
+    end -= substring_length;
     if (end < start)
         return 0;
 
@@ -9265,30 +9266,37 @@ tailmatch(PyObject *self,
     data_self = PyUnicode_DATA(self);
     kind_sub = PyUnicode_KIND(substring);
     data_sub = PyUnicode_DATA(substring);
-    end_sub = PyUnicode_GET_LENGTH(substring) - 1;
+    end_sub = substring_length - 1;
 
     if (direction > 0)
         offset = end;
     else
         offset = start;
 
-    if (PyUnicode_READ(kind_self, data_self, offset) ==
-        PyUnicode_READ(kind_sub, data_sub, 0) &&
-        PyUnicode_READ(kind_self, data_self, offset + end_sub) ==
-        PyUnicode_READ(kind_sub, data_sub, end_sub)) {
+    int match_first = PyUnicode_READ(kind_self, data_self, offset) ==
+                        PyUnicode_READ(kind_sub, data_sub, 0);
+
+    if (match_first) {
+        if (substring_length == 1) {
+            // single-character case
+            return 1;
+        }
+        int match_last = PyUnicode_READ(kind_self, data_self, offset + end_sub) ==
+                        PyUnicode_READ(kind_sub, data_sub, end_sub);
+        if (!match_last && substring_length == 2) {
+            // failing two-character case
+            return 1;
+        }
         /* If both are of the same kind, memcmp is sufficient */
         if (kind_self == kind_sub) {
-            return ! memcmp((char *)data_self +
-                                (offset * PyUnicode_KIND(substring)),
-                            data_sub,
-                            PyUnicode_GET_LENGTH(substring) *
-                                PyUnicode_KIND(substring));
+            return ! memcmp((char *)data_self + (offset * kind_sub),
+                            data_sub, end_sub * kind_sub);
         }
         /* otherwise we have to compare each character by first accessing it */
         else {
-            /* We do not need to compare 0 and len(substring)-1 because
-               the if statement above ensured already that they are equal
-               when we end up here. */
+            /* We do not need to compare 0 and len(substring)-1 because the if
+               statements above ensured already that they are equal when we
+               end up here. */
             for (i = 1; i < end_sub; ++i) {
                 if (PyUnicode_READ(kind_self, data_self, offset + i) !=
                     PyUnicode_READ(kind_sub, data_sub, i))