diff --git a/django/contrib/admin/helpers.py b/django/contrib/admin/helpers.py
index cbe03031a9..604fcd5b26 100644
--- a/django/contrib/admin/helpers.py
+++ b/django/contrib/admin/helpers.py
@@ -1,7 +1,6 @@
 from __future__ import unicode_literals
 
 import json
-import warnings
 
 from django import forms
 from django.conf import settings
@@ -14,7 +13,6 @@ from django.db.models.fields.related import ManyToManyRel
 from django.forms.utils import flatatt
 from django.template.defaultfilters import capfirst, linebreaksbr
 from django.utils import six
-from django.utils.deprecation import RemovedInDjango20Warning
 from django.utils.encoding import force_text
 from django.utils.html import conditional_escape, format_html
 from django.utils.safestring import mark_safe
@@ -218,17 +216,7 @@ class AdminReadonlyField(object):
                     if hasattr(value, "__html__"):
                         result_repr = value
                     else:
-                        result_repr = force_text(value)
-                        if getattr(attr, "allow_tags", False):
-                            warnings.warn(
-                                "Deprecated allow_tags attribute used on %s. "
-                                "Use django.utils.html.format_html(), format_html_join(), "
-                                "or django.utils.safestring.mark_safe() instead." % attr,
-                                RemovedInDjango20Warning
-                            )
-                            result_repr = mark_safe(value)
-                        else:
-                            result_repr = linebreaksbr(result_repr)
+                        result_repr = linebreaksbr(force_text(value))
             else:
                 if isinstance(f.remote_field, ManyToManyRel) and value is not None:
                     result_repr = ", ".join(map(six.text_type, value.all()))
diff --git a/django/contrib/admin/templatetags/admin_list.py b/django/contrib/admin/templatetags/admin_list.py
index ce2a80cbc2..ad6c03ea89 100644
--- a/django/contrib/admin/templatetags/admin_list.py
+++ b/django/contrib/admin/templatetags/admin_list.py
@@ -1,7 +1,6 @@
 from __future__ import unicode_literals
 
 import datetime
-import warnings
 
 from django.contrib.admin.templatetags.admin_urls import add_preserved_filters
 from django.contrib.admin.utils import (
@@ -18,7 +17,6 @@ from django.template.loader import get_template
 from django.templatetags.static import static
 from django.urls import NoReverseMatch
 from django.utils import formats
-from django.utils.deprecation import RemovedInDjango20Warning
 from django.utils.encoding import force_text
 from django.utils.html import format_html
 from django.utils.safestring import mark_safe
@@ -223,17 +221,8 @@ def items_for_result(cl, result, form):
             if f is None or f.auto_created:
                 if field_name == 'action_checkbox':
                     row_classes = ['action-checkbox']
-                allow_tags = getattr(attr, 'allow_tags', False)
                 boolean = getattr(attr, 'boolean', False)
                 result_repr = display_for_value(value, empty_value_display, boolean)
-                if allow_tags:
-                    warnings.warn(
-                        "Deprecated allow_tags attribute used on field {}. "
-                        "Use django.utils.html.format_html(), format_html_join(), "
-                        "or django.utils.safestring.mark_safe() instead.".format(field_name),
-                        RemovedInDjango20Warning
-                    )
-                    result_repr = mark_safe(result_repr)
                 if isinstance(value, (datetime.date, datetime.time)):
                     row_classes.append('nowrap')
             else:
diff --git a/docs/ref/contrib/admin/index.txt b/docs/ref/contrib/admin/index.txt
index 40acb7dd29..b08d17421e 100644
--- a/docs/ref/contrib/admin/index.txt
+++ b/docs/ref/contrib/admin/index.txt
@@ -633,14 +633,6 @@ subclass::
           class PersonAdmin(admin.ModelAdmin):
               list_display = ('first_name', 'last_name', 'colored_name')
 
-      .. deprecated:: 1.9
-
-          In older versions, you could add an ``allow_tags`` attribute to the
-          method to prevent auto-escaping. This attribute is deprecated as it's
-          safer to use :func:`~django.utils.html.format_html`,
-          :func:`~django.utils.html.format_html_join`, or
-          :func:`~django.utils.safestring.mark_safe` instead.
-
     * As some examples have already demonstrated, when using a callable, a
       model method, or a ``ModelAdmin`` method, you can customize the column's
       title by adding a ``short_description`` attribute to the callable.
diff --git a/docs/releases/2.0.txt b/docs/releases/2.0.txt
index d1edbf6180..311a3d6da4 100644
--- a/docs/releases/2.0.txt
+++ b/docs/releases/2.0.txt
@@ -309,3 +309,6 @@ these features.
 
 * The ``callable_obj`` keyword argument to
   ``SimpleTestCase.assertRaisesMessage()`` is removed.
+
+* Support for the ``allow_tags`` attribute on ``ModelAdmin`` methods is
+  removed.
diff --git a/tests/admin_changelist/tests.py b/tests/admin_changelist/tests.py
index b2292a77a0..2f0f6ad46b 100644
--- a/tests/admin_changelist/tests.py
+++ b/tests/admin_changelist/tests.py
@@ -11,11 +11,10 @@ from django.contrib.admin.views.main import ALL_VAR, SEARCH_VAR, ChangeList
 from django.contrib.auth.models import User
 from django.contrib.contenttypes.models import ContentType
 from django.template import Context, Template
-from django.test import TestCase, ignore_warnings, override_settings
+from django.test import TestCase, override_settings
 from django.test.client import RequestFactory
 from django.urls import reverse
 from django.utils import formats, six
-from django.utils.deprecation import RemovedInDjango20Warning
 
 from .admin import (
     BandAdmin, ChildAdmin, ChordsBandAdmin, ConcertAdmin,
@@ -253,34 +252,6 @@ class ChangeListTests(TestCase):
         with self.assertRaises(IncorrectLookupParameters):
             ChangeList(request, Child, *get_changelist_args(m))
 
-    @ignore_warnings(category=RemovedInDjango20Warning)
-    def test_result_list_with_allow_tags(self):
-        """
-        Test for deprecation of allow_tags attribute
-        """
-        new_parent = Parent.objects.create(name='parent')
-        for i in range(2):
-            Child.objects.create(name='name %s' % i, parent=new_parent)
-        request = self.factory.get('/child/')
-        m = ChildAdmin(Child, custom_site)
-
-        def custom_method(self, obj=None):
-            return 'Unsafe html <br />'
-        custom_method.allow_tags = True
-
-        # Add custom method with allow_tags attribute
-        m.custom_method = custom_method
-        m.list_display = ['id', 'name', 'parent', 'custom_method']
-
-        cl = ChangeList(request, Child, *get_changelist_args(m))
-        FormSet = m.get_changelist_formset(request)
-        cl.formset = FormSet(queryset=cl.result_list)
-        template = Template('{% load admin_list %}{% spaceless %}{% result_list cl %}{% endspaceless %}')
-        context = Context({'cl': cl})
-        table_output = template.render(context)
-        custom_field_html = '<td class="field-custom_method">Unsafe html <br /></td>'
-        self.assertInHTML(custom_field_html, table_output)
-
     def test_custom_paginator(self):
         new_parent = Parent.objects.create(name='parent')
         for i in range(200):
diff --git a/tests/admin_views/admin.py b/tests/admin_views/admin.py
index e8a1cf3bff..d85f5de059 100644
--- a/tests/admin_views/admin.py
+++ b/tests/admin_views/admin.py
@@ -447,7 +447,7 @@ class PostAdmin(admin.ModelAdmin):
     readonly_fields = (
         'posted', 'awesomeness_level', 'coolness', 'value',
         'multiline', 'multiline_html', lambda obj: "foo",
-        'multiline_html_allow_tags', 'readonly_content',
+        'readonly_content',
     )
 
     inlines = [
@@ -470,10 +470,6 @@ class PostAdmin(admin.ModelAdmin):
     def multiline_html(self, instance):
         return mark_safe("Multiline<br>\nhtml<br>\ncontent")
 
-    def multiline_html_allow_tags(self, instance):
-        return "Multiline<br>html<br>content<br>with allow tags"
-    multiline_html_allow_tags.allow_tags = True
-
 
 class FieldOverridePostForm(forms.ModelForm):
     model = FieldOverridePost
diff --git a/tests/admin_views/tests.py b/tests/admin_views/tests.py
index c952a9ebf2..a724d57559 100644
--- a/tests/admin_views/tests.py
+++ b/tests/admin_views/tests.py
@@ -35,9 +35,7 @@ from django.urls import NoReverseMatch, resolve, reverse
 from django.utils import formats, six, translation
 from django.utils._os import upath
 from django.utils.cache import get_max_age
-from django.utils.deprecation import (
-    RemovedInDjango20Warning, RemovedInDjango21Warning,
-)
+from django.utils.deprecation import RemovedInDjango21Warning
 from django.utils.encoding import force_bytes, force_text, iri_to_uri
 from django.utils.html import escape
 from django.utils.http import urlencode
@@ -4655,7 +4653,6 @@ class ReadonlyTest(AdminFieldExtractionMixin, TestCase):
     def setUp(self):
         self.client.force_login(self.superuser)
 
-    @ignore_warnings(category=RemovedInDjango20Warning)  # for allow_tags deprecation
     def test_readonly_get(self):
         response = self.client.get(reverse('admin:admin_views_post_add'))
         self.assertEqual(response.status_code, 200)
@@ -4673,12 +4670,6 @@ class ReadonlyTest(AdminFieldExtractionMixin, TestCase):
         self.assertContains(response, 'Multiline<br />test<br />string')
         self.assertContains(response, '<div class="readonly">Multiline<br />html<br />content</div>', html=True)
         self.assertContains(response, 'InlineMultiline<br />test<br />string')
-        # Remove only this last line when the deprecation completes.
-        self.assertContains(
-            response,
-            '<div class="readonly">Multiline<br />html<br />content<br />with allow tags</div>',
-            html=True
-        )
 
         self.assertContains(response, formats.localize(datetime.date.today() - datetime.timedelta(days=7)))
 
@@ -4708,7 +4699,6 @@ class ReadonlyTest(AdminFieldExtractionMixin, TestCase):
         response = self.client.get(reverse('admin:admin_views_post_change', args=(p.pk,)))
         self.assertContains(response, "%d amount of cool" % p.pk)
 
-    @ignore_warnings(category=RemovedInDjango20Warning)  # for allow_tags deprecation
     def test_readonly_text_field(self):
         p = Post.objects.create(
             title="Readonly test", content="test",
@@ -4802,7 +4792,6 @@ class ReadonlyTest(AdminFieldExtractionMixin, TestCase):
         field = self.get_admin_readonly_field(response, 'plotdetails')
         self.assertEqual(field.contents(), '-')  # default empty value
 
-    @ignore_warnings(category=RemovedInDjango20Warning)  # for allow_tags deprecation
     def test_readonly_field_overrides(self):
         """
         Regression test for #22087 - ModelForm Meta overrides are ignored by
@@ -5148,7 +5137,6 @@ class CSSTest(TestCase):
     def setUp(self):
         self.client.force_login(self.superuser)
 
-    @ignore_warnings(category=RemovedInDjango20Warning)  # for allow_tags deprecation
     def test_field_prefix_css_classes(self):
         """
         Fields have a CSS class name with a 'field-' prefix.