diff --git a/src/wp-includes/class-wp-rewrite.php b/src/wp-includes/class-wp-rewrite.php
index e6f768fed1..1107aa9d37 100644
--- a/src/wp-includes/class-wp-rewrite.php
+++ b/src/wp-includes/class-wp-rewrite.php
@@ -841,6 +841,28 @@ class WP_Rewrite {
 		}
 	}
 
+
+	/**
+	 * Removes an existing rewrite tag.
+	 *
+	 * @since 4.5.0
+	 * @access public
+	 *
+	 * @see WP_Rewrite::$rewritecode
+	 * @see WP_Rewrite::$rewritereplace
+	 * @see WP_Rewrite::$queryreplace
+	 *
+	 * @param string $tag Name of the rewrite tag to remove.
+	 */
+	public function remove_rewrite_tag( $tag ) {
+		$position = array_search( $tag, $this->rewritecode );
+		if ( false !== $position && null !== $position ) {
+			unset( $this->rewritecode[ $position ] );
+			unset( $this->rewritereplace[ $position ] );
+			unset( $this->queryreplace[ $position ] );
+		}
+	}
+
 	/**
 	 * Generates rewrite rules from a permalink structure.
 	 *
diff --git a/src/wp-includes/rewrite.php b/src/wp-includes/rewrite.php
index fe6b99adb7..c43abe8de9 100644
--- a/src/wp-includes/rewrite.php
+++ b/src/wp-includes/rewrite.php
@@ -172,6 +172,20 @@ function add_rewrite_tag( $tag, $regex, $query = '' ) {
 	$wp_rewrite->add_rewrite_tag( $tag, $regex, $query );
 }
 
+/**
+ * Removes an existing rewrite tag (like %postname%).
+ *
+ * @since 4.5.0
+ *
+ * @global WP_Rewrite $wp_rewrite WordPress rewrite component.
+ *
+ * @param string $tag Name of the rewrite tag.
+ */
+function remove_rewrite_tag( $tag ) {
+	global $wp_rewrite;
+	$wp_rewrite->remove_rewrite_tag( $tag );
+}
+
 /**
  * Add permalink structure.
  *
diff --git a/tests/phpunit/tests/rewrite/rewriteTags.php b/tests/phpunit/tests/rewrite/rewriteTags.php
new file mode 100644
index 0000000000..a86fcc0ad8
--- /dev/null
+++ b/tests/phpunit/tests/rewrite/rewriteTags.php
@@ -0,0 +1,127 @@
+<?php
+
+/**
+ * @group rewrite
+ */
+class Tests_Rewrite_Tags extends WP_UnitTestCase {
+	protected $rewritecode;
+	protected $rewritereplace;
+	protected $queryreplace;
+
+	public function setUp() {
+		global $wp_rewrite;
+		$this->rewritecode    = $wp_rewrite->rewritecode;
+		$this->rewritereplace = $wp_rewrite->rewritereplace;
+		$this->queryreplace   = $wp_rewrite->queryreplace;
+	}
+
+	public function tearDown() {
+		global $wp_rewrite;
+		$wp_rewrite->rewritecode    = $this->rewritecode;
+		$wp_rewrite->rewritereplace = $this->rewritereplace;
+		$wp_rewrite->queryreplace   = $this->queryreplace;
+	}
+
+	public function _invalid_rewrite_tags() {
+		return array(
+			array( 'foo', 'bar' ),
+			array( '%', 'bar' ),
+			array( '%a', 'bar' ),
+			array( 'a%', 'bar' ),
+			array( '%%', 'bar' ),
+			array( '', 'bar' ),
+		);
+	}
+
+	/**
+	 * @dataProvider _invalid_rewrite_tags
+	 *
+	 * @param string $tag   Rewrite tag.
+	 * @param string $regex Regex.
+	 */
+	public function test_add_rewrite_tag_invalid( $tag, $regex ) {
+		global $wp_rewrite;
+
+		add_rewrite_tag( $tag, $regex );
+		$this->assertNotContains( $tag, $wp_rewrite->rewritecode );
+		$this->assertNotContains( $regex, $wp_rewrite->rewritereplace );
+		$this->assertNotContains( $tag . '=', $wp_rewrite->queryreplace );
+	}
+
+	public function test_add_rewrite_tag_empty_query() {
+		global $wp_rewrite;
+
+		add_rewrite_tag( '%foo%', 'bar' );
+
+		$this->assertSame( array_merge( $this->rewritecode, array( '%foo%' ) ), $wp_rewrite->rewritecode );
+		$this->assertSame( array_merge( $this->rewritereplace, array( 'bar' ) ), $wp_rewrite->rewritereplace );
+		$this->assertSame( array_merge( $this->queryreplace, array( 'foo=' ) ), $wp_rewrite->queryreplace );
+	}
+
+	public function test_add_rewrite_tag_custom_query() {
+		global $wp_rewrite;
+
+		add_rewrite_tag( '%foo%', 'bar', 'baz=' );
+
+		$this->assertSame( array_merge( $this->rewritecode, array( '%foo%' ) ), $wp_rewrite->rewritecode );
+		$this->assertSame( array_merge( $this->rewritereplace, array( 'bar' ) ), $wp_rewrite->rewritereplace );
+		$this->assertSame( array_merge( $this->queryreplace, array( 'baz=' ) ), $wp_rewrite->queryreplace );
+	}
+
+	public function test_add_rewrite_tag_updates_existing() {
+		global $wp_rewrite;
+
+		add_rewrite_tag( '%pagename%', 'foo', 'bar=' );
+		$this->assertContains( '%pagename%', $wp_rewrite->rewritecode );
+		$this->assertContains( 'foo', $wp_rewrite->rewritereplace );
+		$this->assertNotContains( '([^/]+?)', $wp_rewrite->rewritereplace );
+		$this->assertContains( 'bar=', $wp_rewrite->queryreplace );
+		$this->assertNotContains( 'pagename=', $wp_rewrite->queryreplace );
+	}
+
+	public function test_remove_rewrite_tag() {
+		global $wp_rewrite;
+
+		add_rewrite_tag( '%foo%', 'bar', 'baz=' );
+		$this->assertSame( array_merge( $this->rewritecode, array( '%foo%' ) ), $wp_rewrite->rewritecode );
+		$this->assertSame( array_merge( $this->rewritereplace, array( 'bar' ) ), $wp_rewrite->rewritereplace );
+		$this->assertSame( array_merge( $this->queryreplace, array( 'baz=' ) ), $wp_rewrite->queryreplace );
+
+		remove_rewrite_tag( '%foo%' );
+		$this->assertSame( $this->rewritecode, $wp_rewrite->rewritecode );
+		$this->assertSame( $this->rewritereplace, $wp_rewrite->rewritereplace );
+		$this->assertSame( $this->queryreplace, $wp_rewrite->queryreplace );
+	}
+
+	public function test_remove_rewrite_tag_internal_tag() {
+		global $wp_rewrite;
+
+		$this->assertContains( '%post_id%', $wp_rewrite->rewritecode );
+		$this->assertContains( '([0-9]+)', $wp_rewrite->rewritereplace );
+		$this->assertContains( 'p=', $wp_rewrite->queryreplace );
+
+		remove_rewrite_tag( '%post_id%' );
+
+		$this->assertNotContains( '%post_id%', $wp_rewrite->rewritecode );
+		$this->assertNotContains( '([0-9]+)', $wp_rewrite->rewritereplace );
+		$this->assertNotContains( 'p=', $wp_rewrite->queryreplace );
+	}
+
+	public function test_remove_rewrite_tag_only_removes_one_array_value() {
+		global $wp_rewrite;
+
+		add_rewrite_tag( '%foo%', '([0-9]{1,2})', 'post_type=foo&name=' );
+		$this->assertSame( array_merge( $this->rewritecode, array( '%foo%' ) ), $wp_rewrite->rewritecode );
+		$this->assertSame( array_merge( $this->rewritereplace, array( '([0-9]{1,2})' ) ), $wp_rewrite->rewritereplace );
+		$this->assertSame( array_merge( $this->queryreplace, array( 'post_type=foo&name=' ) ), $wp_rewrite->queryreplace );
+
+		remove_rewrite_tag( '%foo%' );
+		$this->assertSame( $this->rewritecode, $wp_rewrite->rewritecode );
+		$this->assertSame( $this->rewritereplace, $wp_rewrite->rewritereplace );
+		$this->assertSame( $this->queryreplace, $wp_rewrite->queryreplace );
+
+		$this->assertNotContains( '%foo%', $wp_rewrite->rewritecode );
+		$this->assertContains( '([0-9]{1,2})', $wp_rewrite->rewritereplace );
+		$this->assertNotContains( 'post_type=foo&name=', $wp_rewrite->queryreplace );
+	}
+}