diff --git a/packages/block-library/src/table-of-contents/index.php b/packages/block-library/src/table-of-contents/index.php
index 744829d3ee05d..3a6ce2e5f2a4e 100644
--- a/packages/block-library/src/table-of-contents/index.php
+++ b/packages/block-library/src/table-of-contents/index.php
@@ -129,7 +129,7 @@ function block_core_table_of_contents_build_list( $tree, $args ) {
 			$pagelink = ! empty( $heading['page'] ) ? add_query_arg( 'page', $heading['page'], $permalink ) : $permalink;
 			$content  = '<a class="wp-block-table-of-contents__entry" href="' . esc_url( $pagelink . $heading['link'] ) . '">' . esc_html( $heading['content'] ) . '</a>';
 		} else {
-			$content = '<span class=wp-block-table-of-contents__entry>' . esc_html( $heading['content'] ) . '</span>';
+			$content = '<span class="wp-block-table-of-contents__entry">' . esc_html( $heading['content'] ) . '</span>';
 		}
 
 		$list .= '<li>' . $content . $children . '</li>';
diff --git a/phpunit/blocks/render-block-table-of-contents-test.php b/phpunit/blocks/render-block-table-of-contents-test.php
index e29c2181813c8..66932e6f328b9 100644
--- a/phpunit/blocks/render-block-table-of-contents-test.php
+++ b/phpunit/blocks/render-block-table-of-contents-test.php
@@ -29,7 +29,7 @@ public static function wpSetUpBeforeClass() {
 		add_post_meta(
 			self::$page->ID,
 			'core_table_of_contents',
-			'[{"content":"Heading text","level":2,"link":"#heading-text"},{"content":"A sub-heading","level":3,"link":"#a-sub-heading"}]',
+			'[{"content":"Heading text","level":2,"link":"#heading-text","page":null},{"content":"A sub-heading","level":3,"link":"#a-sub-heading","page":null},{"content":"Missing anchor","level":2,"link":null,"page":null}]',
 			true
 		);
 	}
@@ -111,5 +111,10 @@ public function test_render_table_of_contents_from_meta() {
 			$new_content,
 			'Failed to render a sub-heading element from meta'
 		);
+		$this->assertStringContainsString(
+			'<span class="wp-block-table-of-contents__entry">Missing anchor</span>',
+			$new_content,
+			'Failed to render a heading element with a missing anchor'
+		);
 	}
 }