diff --git a/webrtc/modules/audio_coding/codecs/audio_format.cc b/webrtc/modules/audio_coding/codecs/audio_format.cc
index bb69cbdb2f..86d5d80042 100644
--- a/webrtc/modules/audio_coding/codecs/audio_format.cc
+++ b/webrtc/modules/audio_coding/codecs/audio_format.cc
@@ -12,7 +12,6 @@
 
 namespace webrtc {
 
-SdpAudioFormat::SdpAudioFormat() = default;
 SdpAudioFormat::SdpAudioFormat(const SdpAudioFormat&) = default;
 SdpAudioFormat::SdpAudioFormat(SdpAudioFormat&&) = default;
 
diff --git a/webrtc/modules/audio_coding/codecs/audio_format.h b/webrtc/modules/audio_coding/codecs/audio_format.h
index 61c0dd9f6f..9b971778f8 100644
--- a/webrtc/modules/audio_coding/codecs/audio_format.h
+++ b/webrtc/modules/audio_coding/codecs/audio_format.h
@@ -23,9 +23,6 @@ namespace webrtc {
 struct SdpAudioFormat {
   using Parameters = std::map<std::string, std::string>;
 
-  // TODO(kwiberg): Get rid of the default constructor when rtc::Optional no
-  // longer requires it.
-  SdpAudioFormat();
   SdpAudioFormat(const SdpAudioFormat&);
   SdpAudioFormat(SdpAudioFormat&&);
   SdpAudioFormat(const char* name, int clockrate_hz, int num_channels);