diff --git a/okhttp/api/android/okhttp.api b/okhttp/api/android/okhttp.api
index 91980d116b2f..3bc83fab92d8 100644
--- a/okhttp/api/android/okhttp.api
+++ b/okhttp/api/android/okhttp.api
@@ -595,6 +595,7 @@ public final class okhttp3/Headers : java/lang/Iterable, kotlin/jvm/internal/mar
 	public static final field EMPTY Lokhttp3/Headers;
 	public final fun -deprecated_size ()I
 	public final fun byteCount ()J
+	public final fun combine (Lokhttp3/Headers;)Lokhttp3/Headers;
 	public fun equals (Ljava/lang/Object;)Z
 	public final fun get (Ljava/lang/String;)Ljava/lang/String;
 	public final fun getDate (Ljava/lang/String;)Ljava/util/Date;
@@ -623,6 +624,8 @@ public final class okhttp3/Headers$Builder {
 	public final fun addUnsafeNonAscii (Ljava/lang/String;Ljava/lang/String;)Lokhttp3/Headers$Builder;
 	public final fun build ()Lokhttp3/Headers;
 	public final fun get (Ljava/lang/String;)Ljava/lang/String;
+	public final synthetic fun minusAssign (Ljava/lang/String;)V
+	public final synthetic fun plusAssign (Lokhttp3/Headers;)V
 	public final fun removeAll (Ljava/lang/String;)Lokhttp3/Headers$Builder;
 	public final fun set (Ljava/lang/String;Ljava/lang/String;)Lokhttp3/Headers$Builder;
 	public final fun set (Ljava/lang/String;Ljava/time/Instant;)Lokhttp3/Headers$Builder;
diff --git a/okhttp/api/jvm/okhttp.api b/okhttp/api/jvm/okhttp.api
index 493b859afb9a..fe4b5698d635 100644
--- a/okhttp/api/jvm/okhttp.api
+++ b/okhttp/api/jvm/okhttp.api
@@ -595,6 +595,7 @@ public final class okhttp3/Headers : java/lang/Iterable, kotlin/jvm/internal/mar
 	public static final field EMPTY Lokhttp3/Headers;
 	public final fun -deprecated_size ()I
 	public final fun byteCount ()J
+	public final fun combine (Lokhttp3/Headers;)Lokhttp3/Headers;
 	public fun equals (Ljava/lang/Object;)Z
 	public final fun get (Ljava/lang/String;)Ljava/lang/String;
 	public final fun getDate (Ljava/lang/String;)Ljava/util/Date;
@@ -623,6 +624,8 @@ public final class okhttp3/Headers$Builder {
 	public final fun addUnsafeNonAscii (Ljava/lang/String;Ljava/lang/String;)Lokhttp3/Headers$Builder;
 	public final fun build ()Lokhttp3/Headers;
 	public final fun get (Ljava/lang/String;)Ljava/lang/String;
+	public final synthetic fun minusAssign (Ljava/lang/String;)V
+	public final synthetic fun plusAssign (Lokhttp3/Headers;)V
 	public final fun removeAll (Ljava/lang/String;)Lokhttp3/Headers$Builder;
 	public final fun set (Ljava/lang/String;Ljava/lang/String;)Lokhttp3/Headers$Builder;
 	public final fun set (Ljava/lang/String;Ljava/time/Instant;)Lokhttp3/Headers$Builder;
diff --git a/okhttp/src/commonJvmAndroid/kotlin/okhttp3/Headers.kt b/okhttp/src/commonJvmAndroid/kotlin/okhttp3/Headers.kt
index 155aec37c584..3f9af8aeda96 100644
--- a/okhttp/src/commonJvmAndroid/kotlin/okhttp3/Headers.kt
+++ b/okhttp/src/commonJvmAndroid/kotlin/okhttp3/Headers.kt
@@ -134,6 +134,20 @@ class Headers internal constructor(
 
   fun newBuilder(): Builder = commonNewBuilder()
 
+  /**
+   * Returns a new headers instance that combines the headers of this instance with `other`. If
+   * this instance has no headers, then `other` is returned. If `other` has no headers, then this
+   * instance is returned. Otherwise, the headers of this instance followed by the headers of
+   * `other` are returned.
+   */
+  @JvmName("combine")
+  operator fun plus(other: Headers): Headers =
+    when {
+      this.size == 0 -> other
+      other.size == 0 -> this
+      else -> Headers(this.namesAndValues + other.namesAndValues)
+    }
+
   /**
    * Returns true if `other` is a `Headers` object with the same headers, with the same casing, in
    * the same order. Note that two headers instances may be *semantically* equal but not equal
@@ -260,6 +274,11 @@ class Headers internal constructor(
      */
     fun addAll(headers: Headers) = commonAddAll(headers)
 
+    @JvmSynthetic
+    operator fun plusAssign(headers: Headers) {
+      addAll(headers)
+    }
+
     /**
      * Add a header with the specified name and formatted date. Does validation of header names and
      * value.
@@ -306,6 +325,11 @@ class Headers internal constructor(
 
     fun removeAll(name: String) = commonRemoveAll(name)
 
+    @JvmSynthetic
+    operator fun minusAssign(name: String) {
+      removeAll(name)
+    }
+
     /**
      * Set a field with the specified value. If the field is not found, it is added. If the field is
      * found, the existing values are replaced.