diff --git a/zerver/lib/actions.py b/zerver/lib/actions.py
index 2eabb32eff..fbabafbd02 100644
--- a/zerver/lib/actions.py
+++ b/zerver/lib/actions.py
@@ -4957,6 +4957,10 @@ def do_revoke_multi_use_invite(multiuse_invite: MultiuseInvite) -> None:
     notify_invites_changed(multiuse_invite.referred_by)
 
 def do_resend_user_invite_email(prereg_user: PreregistrationUser) -> int:
+    # These are two structurally for the caller's code path.
+    assert prereg_user.referred_by is not None
+    assert prereg_user.realm is not None
+
     check_invite_limit(prereg_user.referred_by.realm, 1)
 
     prereg_user.invited_at = timezone_now()
diff --git a/zerver/views/invite.py b/zerver/views/invite.py
index 03a8fad94b..93ec38db5c 100644
--- a/zerver/views/invite.py
+++ b/zerver/views/invite.py
@@ -109,7 +109,9 @@ def resend_user_invite_email(request: HttpRequest, user_profile: UserProfile,
     except PreregistrationUser.DoesNotExist:
         raise JsonableError(_("No such invitation"))
 
-    if (prereg_user.referred_by.realm != user_profile.realm):
+    # Structurally, any invitation the user can actually access should
+    # have a referred_by set for the user who created it.
+    if prereg_user.referred_by is None or prereg_user.referred_by.realm != user_profile.realm:
         raise JsonableError(_("No such invitation"))
 
     timestamp = do_resend_user_invite_email(prereg_user)