diff --git a/quiche/common/quiche_feature_flags_list.h b/quiche/common/quiche_feature_flags_list.h
index 1e52ff0..0f9c864 100755
--- a/quiche/common/quiche_feature_flags_list.h
+++ b/quiche/common/quiche_feature_flags_list.h
@@ -55,7 +55,7 @@
 QUICHE_FLAG(bool, quiche_reloadable_flag_quic_parse_cert_compression_algos_from_chlo, true, true, "If true, parse offered cert compression algorithms from received CHLOs.")
 QUICHE_FLAG(bool, quiche_reloadable_flag_quic_priority_respect_incremental, false, false, "If true, respect the incremental parameter of each stream in QuicWriteBlockedList.")
 QUICHE_FLAG(bool, quiche_reloadable_flag_quic_receive_ack_frequency, false, false, "When true, advertises support for ACK_FREQUENCY and IMMEDIATE_ACK from draft-ietf-quic-ack-frequency-10 and processes them correctly.")
-QUICHE_FLAG(bool, quiche_reloadable_flag_quic_record_tos_byte, false, true, "If true, record TOS byte at QuicPacketReader.")
+QUICHE_FLAG(bool, quiche_reloadable_flag_quic_record_tos_byte, true, true, "If true, record TOS byte at QuicPacketReader.")
 QUICHE_FLAG(bool, quiche_reloadable_flag_quic_require_handshake_confirmation, true, true, "If true, require handshake confirmation for QUIC connections, functionally disabling 0-rtt handshakes.")
 QUICHE_FLAG(bool, quiche_reloadable_flag_quic_test_peer_addr_change_after_normalize, false, false, "If true, QuicConnection::ProcessValidatedPacket will use normalized address to test peer address changes.")
 QUICHE_FLAG(bool, quiche_reloadable_flag_quic_testonly_default_false, false, false, "A testonly reloadable flag that will always default to false.")