diff --git a/pkgs/tools/networking/whois/default.nix b/pkgs/tools/networking/whois/default.nix
index 9855a948783a..fc122ebd2f76 100644
--- a/pkgs/tools/networking/whois/default.nix
+++ b/pkgs/tools/networking/whois/default.nix
@@ -19,6 +19,11 @@ stdenv.mkDerivation rec {
     })
   ];
 
+  env = lib.optionalAttrs stdenv.hostPlatform.isDarwin {
+    # whois fails to link libiconv on Darwin.
+    NIX_LDFLAGS = "-liconv";
+  };
+
   nativeBuildInputs = [ perl gettext pkg-config ];
   buildInputs = [ libidn2 libiconv ];