diff --git a/django/contrib/auth/hashers.py b/django/contrib/auth/hashers.py
index 95b6e000bc..e23ae6243e 100644
--- a/django/contrib/auth/hashers.py
+++ b/django/contrib/auth/hashers.py
@@ -312,7 +312,7 @@ class PBKDF2PasswordHasher(BasePasswordHasher):
     """
 
     algorithm = "pbkdf2_sha256"
-    iterations = 720000
+    iterations = 870000
     digest = hashlib.sha256
 
     def encode(self, password, salt, iterations=None):
diff --git a/docs/releases/5.1.txt b/docs/releases/5.1.txt
index 77cb9fbfc7..37868efde1 100644
--- a/docs/releases/5.1.txt
+++ b/docs/releases/5.1.txt
@@ -42,7 +42,8 @@ Minor features
 :mod:`django.contrib.auth`
 ~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-* ...
+* The default iteration count for the PBKDF2 password hasher is increased from
+  720,000 to 870,000.
 
 :mod:`django.contrib.contenttypes`
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
diff --git a/tests/auth_tests/test_hashers.py b/tests/auth_tests/test_hashers.py
index 643f60ffc7..e0b640a998 100644
--- a/tests/auth_tests/test_hashers.py
+++ b/tests/auth_tests/test_hashers.py
@@ -83,7 +83,7 @@ class TestUtilsHashPass(SimpleTestCase):
         encoded = make_password("lètmein", "seasalt", "pbkdf2_sha256")
         self.assertEqual(
             encoded,
-            "pbkdf2_sha256$720000$seasalt$eDupbcisD1UuIiou3hMuMu8oe/XwnpDw45r6AA5iv0E=",
+            "pbkdf2_sha256$870000$seasalt$wJSpLMQRQz0Dhj/pFpbyjMj71B2gUYp6HJS5AU+32Ac=",
         )
         self.assertTrue(is_password_usable(encoded))
         self.assertTrue(check_password("lètmein", encoded))
@@ -275,8 +275,8 @@ class TestUtilsHashPass(SimpleTestCase):
         encoded = hasher.encode("lètmein", "seasalt2")
         self.assertEqual(
             encoded,
-            "pbkdf2_sha256$720000$"
-            "seasalt2$e8hbsPnTo9qWhT3xYfKWoRth0h0J3360yb/tipPhPtY=",
+            "pbkdf2_sha256$870000$"
+            "seasalt2$nxgnNHRsZWSmi4hRSKq2MRigfaRmjDhH1NH4g2sQRbU=",
         )
         self.assertTrue(hasher.verify("lètmein", encoded))
 
@@ -284,7 +284,7 @@ class TestUtilsHashPass(SimpleTestCase):
         hasher = PBKDF2SHA1PasswordHasher()
         encoded = hasher.encode("lètmein", "seasalt2")
         self.assertEqual(
-            encoded, "pbkdf2_sha1$720000$seasalt2$2DDbzziqCtfldrRSNAaF8oA9OMw="
+            encoded, "pbkdf2_sha1$870000$seasalt2$iFPKnrkYfxxyxaeIqxq+c3nJ/j4="
         )
         self.assertTrue(hasher.verify("lètmein", encoded))