diff --git a/src/cssllc-disable-login.php b/src/cssllc-disable-login.php
index 2293d5a..533412a 100644
--- a/src/cssllc-disable-login.php
+++ b/src/cssllc-disable-login.php
@@ -38,7 +38,7 @@ public static function init() : void {
 			return;
 		}
 
-		if ( constant( 'PHP_SESSION_NONE' ) === session_status() ) {
+		if ( constant( 'PHP_SESSION_NONE' ) === session_status() && ! headers_sent() ) {
 			session_start();
 		}
 
@@ -90,7 +90,7 @@ public function action__login_init() : void {
 	 * @return void
 	 */
 	public function action__wp_login() : void {
-		if ( constant( 'PHP_SESSION_NONE' ) === session_status() ) {
+		if ( constant( 'PHP_SESSION_NONE' ) === session_status() && ! headers_sent() ) {
 			session_start();
 		}