diff --git a/esphome/__main__.py b/esphome/__main__.py
index 3549686d01..05de49e8d0 100644
--- a/esphome/__main__.py
+++ b/esphome/__main__.py
@@ -163,7 +163,7 @@ def compile_program(args, config):
 def upload_using_esptool(config, port):
     path = CORE.firmware_bin
     cmd = ['esptool.py', '--before', 'default_reset', '--after', 'hard_reset',
-           '--baud', config[CONF_ESPHOME][CONF_PLATFORMIO_OPTIONS].get('upload_speed', 115200),
+           '--baud', str(config[CONF_ESPHOME][CONF_PLATFORMIO_OPTIONS].get('upload_speed', 115200)),
            '--chip', 'esp8266', '--port', port, 'write_flash', '0x0', path]
 
     if os.environ.get('ESPHOME_USE_SUBPROCESS') is None: