diff --git a/quiche/quic/core/congestion_control/tcp_cubic_sender_bytes.cc b/quiche/quic/core/congestion_control/tcp_cubic_sender_bytes.cc
index af0a5a9..bc61d87 100644
--- a/quiche/quic/core/congestion_control/tcp_cubic_sender_bytes.cc
+++ b/quiche/quic/core/congestion_control/tcp_cubic_sender_bytes.cc
@@ -55,47 +55,18 @@
 
 void TcpCubicSenderBytes::SetFromConfig(const QuicConfig& config,
                                         Perspective perspective) {
-  if (perspective == Perspective::IS_SERVER) {
-    if (!GetQuicReloadableFlag(quic_unified_iw_options)) {
-      if (config.HasReceivedConnectionOptions() &&
-          ContainsQuicTag(config.ReceivedConnectionOptions(), kIW03)) {
-        // Initial window experiment.
-        SetInitialCongestionWindowInPackets(3);
-      }
-      if (config.HasReceivedConnectionOptions() &&
-          ContainsQuicTag(config.ReceivedConnectionOptions(), kIW10)) {
-        // Initial window experiment.
-        SetInitialCongestionWindowInPackets(10);
-      }
-      if (config.HasReceivedConnectionOptions() &&
-          ContainsQuicTag(config.ReceivedConnectionOptions(), kIW20)) {
-        // Initial window experiment.
-        SetInitialCongestionWindowInPackets(20);
-      }
-      if (config.HasReceivedConnectionOptions() &&
-          ContainsQuicTag(config.ReceivedConnectionOptions(), kIW50)) {
-        // Initial window experiment.
-        SetInitialCongestionWindowInPackets(50);
-      }
-      if (config.HasReceivedConnectionOptions() &&
-          ContainsQuicTag(config.ReceivedConnectionOptions(), kMIN1)) {
-        // Min CWND experiment.
-        SetMinCongestionWindowInPackets(1);
-      }
-    }
-    if (config.HasReceivedConnectionOptions() &&
-        ContainsQuicTag(config.ReceivedConnectionOptions(), kMIN4)) {
+  if (perspective == Perspective::IS_SERVER &&
+      config.HasReceivedConnectionOptions()) {
+    if (ContainsQuicTag(config.ReceivedConnectionOptions(), kMIN4)) {
       // Min CWND of 4 experiment.
       min4_mode_ = true;
       SetMinCongestionWindowInPackets(1);
     }
-    if (config.HasReceivedConnectionOptions() &&
-        ContainsQuicTag(config.ReceivedConnectionOptions(), kSSLR)) {
+    if (ContainsQuicTag(config.ReceivedConnectionOptions(), kSSLR)) {
       // Slow Start Fast Exit experiment.
       slow_start_large_reduction_ = true;
     }
-    if (config.HasReceivedConnectionOptions() &&
-        ContainsQuicTag(config.ReceivedConnectionOptions(), kNPRR)) {
+    if (ContainsQuicTag(config.ReceivedConnectionOptions(), kNPRR)) {
       // Use unity pacing instead of PRR.
       no_prr_ = true;
     }
diff --git a/quiche/quic/core/congestion_control/tcp_cubic_sender_bytes_test.cc b/quiche/quic/core/congestion_control/tcp_cubic_sender_bytes_test.cc
index ad56c2f..3ac1ba2 100644
--- a/quiche/quic/core/congestion_control/tcp_cubic_sender_bytes_test.cc
+++ b/quiche/quic/core/congestion_control/tcp_cubic_sender_bytes_test.cc
@@ -545,7 +545,6 @@
 }
 
 TEST_F(TcpCubicSenderBytesTest, ConfigureMaxInitialWindow) {
-  SetQuicReloadableFlag(quic_unified_iw_options, false);
   QuicConfig config;
 
   // Verify that kCOPT: kIW10 forces the congestion window to the default of 10.
diff --git a/quiche/quic/core/http/end_to_end_test.cc b/quiche/quic/core/http/end_to_end_test.cc
index 706e23a..17bb93b 100644
--- a/quiche/quic/core/http/end_to_end_test.cc
+++ b/quiche/quic/core/http/end_to_end_test.cc
@@ -3499,7 +3499,6 @@
 }
 
 TEST_P(EndToEndTest, NegotiatedInitialCongestionWindow) {
-  SetQuicReloadableFlag(quic_unified_iw_options, true);
   client_extra_copts_.push_back(kIW03);
 
   ASSERT_TRUE(Initialize());
diff --git a/quiche/quic/core/quic_flags_list.h b/quiche/quic/core/quic_flags_list.h
index 9363f9c..c6ea94e 100644
--- a/quiche/quic/core/quic_flags_list.h
+++ b/quiche/quic/core/quic_flags_list.h
@@ -87,8 +87,6 @@
 QUIC_FLAG(quic_restart_flag_quic_abstract_connection_id_generator, true)
 // When true, defaults to BBR congestion control instead of Cubic.
 QUIC_FLAG(quic_reloadable_flag_quic_default_to_bbr, false)
-// When true, set the initial congestion control window from connection options in QuicSentPacketManager rather than TcpCubicSenderBytes.
-QUIC_FLAG(quic_reloadable_flag_quic_unified_iw_options, true)
 // When true, support draft-ietf-quic-v2-01
 QUIC_FLAG(quic_reloadable_flag_quic_enable_version_2_draft_01, false)
 // When true, the BBR4 copt sets the extra_acked window to 20 RTTs and BBR5 sets it to 40 RTTs.
diff --git a/quiche/quic/core/quic_sent_packet_manager.cc b/quiche/quic/core/quic_sent_packet_manager.cc
index 557eace..88039a5 100644
--- a/quiche/quic/core/quic_sent_packet_manager.cc
+++ b/quiche/quic/core/quic_sent_packet_manager.cc
@@ -150,27 +150,21 @@
   }
 
   // Initial window.
-  if (GetQuicReloadableFlag(quic_unified_iw_options)) {
-    if (config.HasClientRequestedIndependentOption(kIW03, perspective)) {
-      QUIC_RELOADABLE_FLAG_COUNT_N(quic_unified_iw_options, 1, 4);
-      initial_congestion_window_ = 3;
-      send_algorithm_->SetInitialCongestionWindowInPackets(3);
-    }
-    if (config.HasClientRequestedIndependentOption(kIW10, perspective)) {
-      QUIC_RELOADABLE_FLAG_COUNT_N(quic_unified_iw_options, 2, 4);
-      initial_congestion_window_ = 10;
-      send_algorithm_->SetInitialCongestionWindowInPackets(10);
-    }
-    if (config.HasClientRequestedIndependentOption(kIW20, perspective)) {
-      QUIC_RELOADABLE_FLAG_COUNT_N(quic_unified_iw_options, 3, 4);
-      initial_congestion_window_ = 20;
-      send_algorithm_->SetInitialCongestionWindowInPackets(20);
-    }
-    if (config.HasClientRequestedIndependentOption(kIW50, perspective)) {
-      QUIC_RELOADABLE_FLAG_COUNT_N(quic_unified_iw_options, 4, 4);
-      initial_congestion_window_ = 50;
-      send_algorithm_->SetInitialCongestionWindowInPackets(50);
-    }
+  if (config.HasClientRequestedIndependentOption(kIW03, perspective)) {
+    initial_congestion_window_ = 3;
+    send_algorithm_->SetInitialCongestionWindowInPackets(3);
+  }
+  if (config.HasClientRequestedIndependentOption(kIW10, perspective)) {
+    initial_congestion_window_ = 10;
+    send_algorithm_->SetInitialCongestionWindowInPackets(10);
+  }
+  if (config.HasClientRequestedIndependentOption(kIW20, perspective)) {
+    initial_congestion_window_ = 20;
+    send_algorithm_->SetInitialCongestionWindowInPackets(20);
+  }
+  if (config.HasClientRequestedIndependentOption(kIW50, perspective)) {
+    initial_congestion_window_ = 50;
+    send_algorithm_->SetInitialCongestionWindowInPackets(50);
   }
   if (config.HasClientRequestedIndependentOption(kBWS5, perspective)) {
     initial_congestion_window_ = 10;