diff --git a/doc/release/upcoming_changes/19539.expired.rst b/doc/release/upcoming_changes/19539.expired.rst
new file mode 100644
index 000000000000..6e94f175d85c
--- /dev/null
+++ b/doc/release/upcoming_changes/19539.expired.rst
@@ -0,0 +1,2 @@
+* Using the strings ``"Bytes0"``, ``"Datetime64"``, ``"Str0"``, ``"Uint32"``,
+  and ``"Uint64"`` as a dtype will now raise a ``TypeError``.
\ No newline at end of file
diff --git a/numpy/core/_type_aliases.py b/numpy/core/_type_aliases.py
index 67addef483f6..3765a0d34e18 100644
--- a/numpy/core/_type_aliases.py
+++ b/numpy/core/_type_aliases.py
@@ -115,15 +115,6 @@ def _add_aliases():
         # add forward, reverse, and string mapping to numarray
         sctypeDict[char] = info.type
 
-    # Add deprecated numeric-style type aliases manually, at some point
-    # we may want to deprecate the lower case "bytes0" version as well.
-    for name in ["Bytes0", "Datetime64", "Str0", "Uint32", "Uint64"]:
-        if english_lower(name) not in allTypes:
-            # Only one of Uint32 or Uint64, aliases of `np.uintp`, was (and is) defined, note that this
-            # is not UInt32/UInt64 (capital i), which is removed.
-            continue
-        allTypes[name] = allTypes[english_lower(name)]
-        sctypeDict[name] = sctypeDict[english_lower(name)]
 
 _add_aliases()
 
diff --git a/numpy/core/src/multiarray/descriptor.c b/numpy/core/src/multiarray/descriptor.c
index 50964dab8f35..90453e38fd0e 100644
--- a/numpy/core/src/multiarray/descriptor.c
+++ b/numpy/core/src/multiarray/descriptor.c
@@ -1723,22 +1723,6 @@ _convert_from_str(PyObject *obj, int align)
             goto fail;
         }
 
-        /* Check for a deprecated Numeric-style typecode */
-        /* `Uint` has deliberately weird uppercasing */
-        char *dep_tps[] = {"Bytes", "Datetime64", "Str", "Uint"};
-        int ndep_tps = sizeof(dep_tps) / sizeof(dep_tps[0]);
-        for (int i = 0; i < ndep_tps; ++i) {
-            char *dep_tp = dep_tps[i];
-
-            if (strncmp(type, dep_tp, strlen(dep_tp)) == 0) {
-                /* Deprecated 2020-06-09, NumPy 1.20 */
-                if (DEPRECATE("Numeric-style type codes are "
-                              "deprecated and will result in "
-                              "an error in the future.") < 0) {
-                    goto fail;
-                }
-            }
-        }
         /*
          * Probably only ever dispatches to `_convert_from_type`, but who
          * knows what users are injecting into `np.typeDict`.
diff --git a/numpy/core/tests/test_deprecations.py b/numpy/core/tests/test_deprecations.py
index 42e632e4aa2a..44a3ed74a1dc 100644
--- a/numpy/core/tests/test_deprecations.py
+++ b/numpy/core/tests/test_deprecations.py
@@ -314,21 +314,6 @@ def test_insufficient_width_negative(self):
         self.assert_deprecated(np.binary_repr, args=args, kwargs=kwargs)
 
 
-class TestNumericStyleTypecodes(_DeprecationTestCase):
-    """
-    Most numeric style typecodes were previously deprecated (and removed)
-    in 1.20. This also deprecates the remaining ones.
-    """
-    # 2020-06-09, NumPy 1.20
-    def test_all_dtypes(self):
-        deprecated_types = ['Bytes0', 'Datetime64', 'Str0']
-        # Depending on intp size, either Uint32 or Uint64 is defined:
-        deprecated_types.append(f"U{np.dtype(np.intp).name}")
-        for dt in deprecated_types:
-            self.assert_deprecated(np.dtype, exceptions=(TypeError,),
-                                   args=(dt,))
-
-
 class TestDTypeAttributeIsDTypeDeprecation(_DeprecationTestCase):
     # Deprecated 2021-01-05, NumPy 1.21
     message = r".*`.dtype` attribute"
diff --git a/numpy/core/tests/test_dtype.py b/numpy/core/tests/test_dtype.py
index 4f52268f57a4..23269f01bebe 100644
--- a/numpy/core/tests/test_dtype.py
+++ b/numpy/core/tests/test_dtype.py
@@ -109,9 +109,12 @@ def test_richcompare_invalid_dtype_comparison(self, operation):
             operation(np.dtype(np.int32), 7)
 
     @pytest.mark.parametrize("dtype",
-             ['Bool', 'Complex32', 'Complex64', 'Float16', 'Float32', 'Float64',
-              'Int8', 'Int16', 'Int32', 'Int64', 'Object0', 'Timedelta64',
-              'UInt8', 'UInt16', 'UInt32', 'UInt64', 'Void0',
+             ['Bool', 'Bytes0', 'Complex32', 'Complex64',
+              'Datetime64', 'Float16', 'Float32', 'Float64',
+              'Int8', 'Int16', 'Int32', 'Int64', 
+              'Object0', 'Str0', 'Timedelta64',
+              'UInt8', 'UInt16', 'Uint32', 'UInt32', 
+              'Uint64', 'UInt64', 'Void0',
               "Float128", "Complex128"])
     def test_numeric_style_types_are_invalid(self, dtype):
         with assert_raises(TypeError):