diff --git a/templates/corporate/for/education.html b/templates/corporate/for/education.html
index 9ff67c0a1b..6c2c0255a3 100644
--- a/templates/corporate/for/education.html
+++ b/templates/corporate/for/education.html
@@ -304,7 +304,7 @@
                                 <hr />
                                 <ul class="feature-list">
                                     <li>Unlimited search history</li>
-                                    <li>File storage up to 10 GB per user</li>
+                                    <li>File storage up to 5 GB per user</li>
                                     <li><a href="/help/message-retention-policy">Message retention policies</a></li>
                                     <li>Brand Zulip with your logo</li>
                                     <li>Priority commercial support</li>
diff --git a/templates/corporate/pricing_model.html b/templates/corporate/pricing_model.html
index fa1469cd61..68be58a894 100644
--- a/templates/corporate/pricing_model.html
+++ b/templates/corporate/pricing_model.html
@@ -67,7 +67,7 @@
                             <h2>Standard</h2>
                             <ul class="feature-list">
                                 <li><span>Unlimited search history</span></li>
-                                <li><span>File storage up to 10 GB per user</span></li>
+                                <li><span>File storage up to 5 GB per user</span></li>
                                 <li><span><a href="/help/message-retention-policy">Message retention policies</a></span></li>
                                 <li><span>Brand Zulip with your logo</span></li>
                                 <li><span>Priority commercial support</span></li>
diff --git a/zerver/models/realms.py b/zerver/models/realms.py
index 366909ed0b..8689cb153e 100644
--- a/zerver/models/realms.py
+++ b/zerver/models/realms.py
@@ -511,7 +511,7 @@ class Realm(models.Model):  # type: ignore[django-manager-missing] # django-stub
     ]
 
     UPLOAD_QUOTA_LIMITED = 5
-    UPLOAD_QUOTA_STANDARD = 50
+    UPLOAD_QUOTA_STANDARD_FREE = 50
     custom_upload_quota_gb = models.IntegerField(null=True)
 
     VIDEO_CHAT_PROVIDERS = {
@@ -836,17 +836,24 @@ class Realm(models.Model):  # type: ignore[django-manager-missing] # django-stub
         if self.custom_upload_quota_gb is not None:
             return self.custom_upload_quota_gb
 
-        plan_type = self.plan_type
-        if plan_type == Realm.PLAN_TYPE_PLUS:
-            return Realm.UPLOAD_QUOTA_STANDARD
-        elif plan_type == Realm.PLAN_TYPE_STANDARD:
-            return Realm.UPLOAD_QUOTA_STANDARD
-        elif plan_type == Realm.PLAN_TYPE_SELF_HOSTED:
+        if not settings.CORPORATE_ENABLED:
             return None
-        elif plan_type == Realm.PLAN_TYPE_STANDARD_FREE:
-            return Realm.UPLOAD_QUOTA_STANDARD
-        elif plan_type == Realm.PLAN_TYPE_LIMITED:
+
+        plan_type = self.plan_type
+        if plan_type == Realm.PLAN_TYPE_SELF_HOSTED:  # nocoverage
+            return None
+        if plan_type == Realm.PLAN_TYPE_LIMITED:
             return Realm.UPLOAD_QUOTA_LIMITED
+        elif plan_type == Realm.PLAN_TYPE_STANDARD_FREE:
+            return Realm.UPLOAD_QUOTA_STANDARD_FREE
+        elif plan_type in [Realm.PLAN_TYPE_STANDARD, Realm.PLAN_TYPE_PLUS]:
+            from corporate.lib.stripe import get_seat_count
+
+            # Paying customers with few users should get a reasonable minimum quota.
+            return max(
+                get_seat_count(self) * settings.UPLOAD_QUOTA_PER_USER_GB,
+                Realm.UPLOAD_QUOTA_STANDARD_FREE,
+            )
         else:
             raise AssertionError("Invalid plan type")
 
diff --git a/zerver/tests/test_realm.py b/zerver/tests/test_realm.py
index 1806610ffe..8f3e31b594 100644
--- a/zerver/tests/test_realm.py
+++ b/zerver/tests/test_realm.py
@@ -5,7 +5,7 @@ import re
 import string
 from datetime import datetime, timedelta
 from typing import Any, Dict, List, Union
-from unittest import mock
+from unittest import mock, skipUnless
 
 import orjson
 from django.conf import settings
@@ -15,6 +15,7 @@ from typing_extensions import override
 
 from confirmation.models import Confirmation, create_confirmation_link
 from zerver.actions.create_realm import do_change_realm_subdomain, do_create_realm
+from zerver.actions.create_user import do_create_user
 from zerver.actions.message_send import (
     internal_send_huddle_message,
     internal_send_private_message,
@@ -60,6 +61,9 @@ from zerver.models.realms import get_realm
 from zerver.models.streams import get_stream
 from zerver.models.users import get_system_bot, get_user_profile_by_id
 
+if settings.ZILENCER_ENABLED:
+    from corporate.lib.stripe import get_seat_count
+
 
 class RealmTest(ZulipTestCase):
     def assert_user_profile_cache_gets_new_name(
@@ -909,8 +913,22 @@ class RealmTest(ZulipTestCase):
         self.assertEqual(realm_audit_log.acting_user, iago)
         self.assertEqual(realm.org_type, Realm.ORG_TYPES["government"]["id"])
 
+    @skipUnless(settings.ZILENCER_ENABLED, "requires zilencer")
     def test_change_realm_plan_type(self) -> None:
         realm = get_realm("zulip")
+
+        # Create additional user, so that the realm has a lot of seats for the purposes
+        # of upload quota calculation.
+        for count in range(10):
+            do_create_user(
+                f"email{count}@example.com",
+                f"password {count}",
+                realm,
+                "name",
+                role=UserProfile.ROLE_MEMBER,
+                acting_user=None,
+            )
+
         iago = self.example_user("iago")
         self.assertEqual(realm.plan_type, Realm.PLAN_TYPE_SELF_HOSTED)
         self.assertEqual(realm.max_invites, settings.INVITES_DEFAULT_REALM_DAILY_MAX)
@@ -938,7 +956,9 @@ class RealmTest(ZulipTestCase):
         self.assertEqual(realm.plan_type, Realm.PLAN_TYPE_STANDARD)
         self.assertEqual(realm.max_invites, Realm.INVITES_STANDARD_REALM_DAILY_MAX)
         self.assertEqual(realm.message_visibility_limit, None)
-        self.assertEqual(realm.upload_quota_gb, Realm.UPLOAD_QUOTA_STANDARD)
+        self.assertEqual(
+            realm.upload_quota_gb, get_seat_count(realm) * settings.UPLOAD_QUOTA_PER_USER_GB
+        )
         everyone_system_group = UserGroup.objects.get(name=SystemGroups.EVERYONE, realm=realm)
         self.assertEqual(realm.can_access_all_users_group_id, everyone_system_group.id)
 
@@ -956,7 +976,7 @@ class RealmTest(ZulipTestCase):
         self.assertEqual(realm.plan_type, Realm.PLAN_TYPE_STANDARD_FREE)
         self.assertEqual(realm.max_invites, Realm.INVITES_STANDARD_REALM_DAILY_MAX)
         self.assertEqual(realm.message_visibility_limit, None)
-        self.assertEqual(realm.upload_quota_gb, Realm.UPLOAD_QUOTA_STANDARD)
+        self.assertEqual(realm.upload_quota_gb, Realm.UPLOAD_QUOTA_STANDARD_FREE)
 
         do_change_realm_plan_type(realm, Realm.PLAN_TYPE_LIMITED, acting_user=iago)
         do_change_realm_plan_type(realm, Realm.PLAN_TYPE_PLUS, acting_user=iago)
@@ -964,7 +984,9 @@ class RealmTest(ZulipTestCase):
         self.assertEqual(realm.plan_type, Realm.PLAN_TYPE_PLUS)
         self.assertEqual(realm.max_invites, Realm.INVITES_STANDARD_REALM_DAILY_MAX)
         self.assertEqual(realm.message_visibility_limit, None)
-        self.assertEqual(realm.upload_quota_gb, Realm.UPLOAD_QUOTA_STANDARD)
+        self.assertEqual(
+            realm.upload_quota_gb, get_seat_count(realm) * settings.UPLOAD_QUOTA_PER_USER_GB
+        )
 
         do_change_realm_permission_group_setting(
             realm, "can_access_all_users_group", members_system_group, acting_user=None
@@ -974,7 +996,9 @@ class RealmTest(ZulipTestCase):
         self.assertEqual(realm.plan_type, Realm.PLAN_TYPE_STANDARD)
         self.assertEqual(realm.max_invites, Realm.INVITES_STANDARD_REALM_DAILY_MAX)
         self.assertEqual(realm.message_visibility_limit, None)
-        self.assertEqual(realm.upload_quota_gb, Realm.UPLOAD_QUOTA_STANDARD)
+        self.assertEqual(
+            realm.upload_quota_gb, get_seat_count(realm) * settings.UPLOAD_QUOTA_PER_USER_GB
+        )
         self.assertEqual(realm.can_access_all_users_group_id, everyone_system_group.id)
 
         # Test that custom_upload_quota_gb overrides the default upload_quota_gb
diff --git a/zproject/default_settings.py b/zproject/default_settings.py
index c00c1d7186..edc02eff8f 100644
--- a/zproject/default_settings.py
+++ b/zproject/default_settings.py
@@ -167,6 +167,9 @@ LOCAL_UPLOADS_DIR: Optional[str] = None
 LOCAL_AVATARS_DIR: Optional[str] = None
 LOCAL_FILES_DIR: Optional[str] = None
 MAX_FILE_UPLOAD_SIZE = 25
+# How many GB an organization on a paid plan can upload per user,
+# on zulipchat.com.
+UPLOAD_QUOTA_PER_USER_GB = 5
 
 # Jitsi Meet video call integration; set to None to disable integration.
 JITSI_SERVER_URL: Optional[str] = "https://meet.jit.si"