diff --git a/api/call/transport.h b/api/call/transport.h
index 6cb4c1107d..8bff28825d 100644
--- a/api/call/transport.h
+++ b/api/call/transport.h
@@ -14,8 +14,6 @@
 #include <stddef.h>
 #include <stdint.h>
 
-#include <vector>
-
 #include "api/ref_counted_base.h"
 #include "api/scoped_refptr.h"
 
@@ -31,8 +29,6 @@ struct PacketOptions {
   // A 16 bits positive id. Negative ids are invalid and should be interpreted
   // as packet_id not being set.
   int packet_id = -1;
-  // Deprecated: use `additional_data` instead of `application_data`.
-  std::vector<uint8_t> application_data;
   // Additional data bound to the RTP packet for use in application code,
   // outside of WebRTC.
   rtc::scoped_refptr<rtc::RefCountedBase> additional_data;
diff --git a/modules/rtp_rtcp/source/deprecated/deprecated_rtp_sender_egress.cc b/modules/rtp_rtcp/source/deprecated/deprecated_rtp_sender_egress.cc
index a4cc10bb90..3f7d22c498 100644
--- a/modules/rtp_rtcp/source/deprecated/deprecated_rtp_sender_egress.cc
+++ b/modules/rtp_rtcp/source/deprecated/deprecated_rtp_sender_egress.cc
@@ -176,8 +176,6 @@ void DEPRECATED_RtpSenderEgress::SendPacket(
     AddPacketToTransportFeedback(*packet_id, *packet, pacing_info);
   }
 
-  options.application_data.assign(packet->application_data().begin(),
-                                  packet->application_data().end());
   options.additional_data = packet->additional_data();
 
   if (packet->packet_type() != RtpPacketMediaType::kPadding &&
diff --git a/modules/rtp_rtcp/source/rtp_packet_received.h b/modules/rtp_rtcp/source/rtp_packet_received.h
index 64348bdce2..c895313755 100644
--- a/modules/rtp_rtcp/source/rtp_packet_received.h
+++ b/modules/rtp_rtcp/source/rtp_packet_received.h
@@ -13,7 +13,6 @@
 #include <stdint.h>
 
 #include <utility>
-#include <vector>
 
 #include "api/array_view.h"
 #include "api/ref_counted_base.h"
@@ -57,16 +56,7 @@ class RtpPacketReceived : public RtpPacket {
   }
 
   // An application can attach arbitrary data to an RTP packet using
-  // `application_data` or `additional_data`.
-  // The additional data does not affect WebRTC processing.
-  RTC_DEPRECATED
-  rtc::ArrayView<const uint8_t> application_data() const {
-    return application_data_;
-  }
-  RTC_DEPRECATED
-  void set_application_data(rtc::ArrayView<const uint8_t> data) {
-    application_data_.assign(data.begin(), data.end());
-  }
+  // `additional_data`. The additional data does not affect WebRTC processing.
   rtc::scoped_refptr<rtc::RefCountedBase> additional_data() const {
     return additional_data_;
   }
@@ -79,7 +69,6 @@ class RtpPacketReceived : public RtpPacket {
   int payload_type_frequency_ = 0;
   bool recovered_ = false;
   rtc::scoped_refptr<rtc::RefCountedBase> additional_data_;
-  std::vector<uint8_t> application_data_;
 };
 
 }  // namespace webrtc
diff --git a/modules/rtp_rtcp/source/rtp_packet_to_send.h b/modules/rtp_rtcp/source/rtp_packet_to_send.h
index 396198fed8..2411deac49 100644
--- a/modules/rtp_rtcp/source/rtp_packet_to_send.h
+++ b/modules/rtp_rtcp/source/rtp_packet_to_send.h
@@ -14,7 +14,6 @@
 #include <stdint.h>
 
 #include <utility>
-#include <vector>
 
 #include "absl/types/optional.h"
 #include "api/array_view.h"
@@ -70,15 +69,7 @@ class RtpPacketToSend : public RtpPacket {
   bool allow_retransmission() { return allow_retransmission_; }
 
   // An application can attach arbitrary data to an RTP packet using
-  // `application_data` or `additional_data`.
-  // The additional data does not affect WebRTC processing.
-  rtc::ArrayView<const uint8_t> application_data() const {
-    return application_data_;
-  }
-
-  void set_application_data(rtc::ArrayView<const uint8_t> data) {
-    application_data_.assign(data.begin(), data.end());
-  }
+  // `additional_data`. The additional data does not affect WebRTC processing.
   rtc::scoped_refptr<rtc::RefCountedBase> additional_data() const {
     return additional_data_;
   }
@@ -134,9 +125,6 @@ class RtpPacketToSend : public RtpPacket {
   absl::optional<RtpPacketMediaType> packet_type_;
   bool allow_retransmission_ = false;
   absl::optional<uint16_t> retransmitted_sequence_number_;
-  // TODO(danilchap): Remove applicaion_data_ when application switched to use
-  // additional_data instead.
-  std::vector<uint8_t> application_data_;
   rtc::scoped_refptr<rtc::RefCountedBase> additional_data_;
   bool is_first_packet_of_frame_ = false;
   bool is_key_frame_ = false;
diff --git a/modules/rtp_rtcp/source/rtp_sender.cc b/modules/rtp_rtcp/source/rtp_sender.cc
index 510c5122c9..ac20454a0f 100644
--- a/modules/rtp_rtcp/source/rtp_sender.cc
+++ b/modules/rtp_rtcp/source/rtp_sender.cc
@@ -809,8 +809,7 @@ std::unique_ptr<RtpPacketToSend> RTPSender::BuildRtxPacket(
   auto payload = packet.payload();
   memcpy(rtx_payload + kRtxHeaderSize, payload.data(), payload.size());
 
-  // Add original application data.
-  rtx_packet->set_application_data(packet.application_data());
+  // Add original additional data.
   rtx_packet->set_additional_data(packet.additional_data());
 
   // Copy capture time so e.g. TransmissionOffset is correctly set.
diff --git a/modules/rtp_rtcp/source/rtp_sender_egress.cc b/modules/rtp_rtcp/source/rtp_sender_egress.cc
index fc628217d9..48f536c6bb 100644
--- a/modules/rtp_rtcp/source/rtp_sender_egress.cc
+++ b/modules/rtp_rtcp/source/rtp_sender_egress.cc
@@ -250,8 +250,6 @@ void RtpSenderEgress::SendPacket(RtpPacketToSend* packet,
     AddPacketToTransportFeedback(*packet_id, *packet, pacing_info);
   }
 
-  options.application_data.assign(packet->application_data().begin(),
-                                  packet->application_data().end());
   options.additional_data = packet->additional_data();
 
   if (packet->packet_type() != RtpPacketMediaType::kPadding &&