diff --git src/wp-content/themes/twentyseventeen/functions.php src/wp-content/themes/twentyseventeen/functions.php
index a41d317e4..c7902dbcb 100644
--- src/wp-content/themes/twentyseventeen/functions.php
+++ src/wp-content/themes/twentyseventeen/functions.php
@@ -502,6 +502,24 @@ function twentyseventeen_front_page_template( $template ) {
 add_filter( 'frontpage_template',  'twentyseventeen_front_page_template' );
 
 /**
+ * Whether the featured image should be shown.
+ *
+ * @since Twenty Seventeen 1.1
+ *
+ * @return bool Whether the post thumbnail should be shown.
+ */
+function twentyseventeen_should_show_featured_image() {
+	$show = has_post_thumbnail() && ( is_single() || ( is_page() && ! twentyseventeen_is_frontpage() ) );
+
+	/**
+	 * Filter whether the featured image should be shown.
+	 *
+	 * @param bool $show Whether to show the featured image.
+	 */
+	return apply_filters( 'twentyseventeen_should_show_featured_image', $show );
+}
+
+/**
  * Implement the Custom Header feature.
  */
 require get_parent_theme_file_path( '/inc/custom-header.php' );
diff --git src/wp-content/themes/twentyseventeen/header.php src/wp-content/themes/twentyseventeen/header.php
index 30d7d2a7c..ba989feec 100644
--- src/wp-content/themes/twentyseventeen/header.php
+++ src/wp-content/themes/twentyseventeen/header.php
@@ -42,7 +42,7 @@
 
 	<?php
 	// If a regular post or page, and not the front page, show the featured image.
-	if ( has_post_thumbnail() && ( is_single() || ( is_page() && ! twentyseventeen_is_frontpage() ) ) ) :
+	if ( twentyseventeen_should_show_featured_image() ) :
 		echo '<div class="single-featured-image-header">';
 		the_post_thumbnail( 'twentyseventeen-featured-image' );
 		echo '</div><!-- .single-featured-image-header -->';