diff --git a/esphome/components/esphome/ota/__init__.py b/esphome/components/esphome/ota/__init__.py
index 1aced2847b..942704dfef 100644
--- a/esphome/components/esphome/ota/__init__.py
+++ b/esphome/components/esphome/ota/__init__.py
@@ -290,6 +290,11 @@ FILTER_SOURCE_FILES = filter_source_files_from_defines(
 )
 
 
+def enable_deflate() -> None:
+    """Compile the on-the-fly inflater for compressed uploads."""
+    cg.add_define("USE_OTA_DEFLATE")
+
+
 @coroutine_with_priority(CoroPriority.OTA_UPDATES)
 async def to_code(config: ConfigType) -> None:
     var = cg.new_Pvariable(config[CONF_ID])
@@ -310,7 +315,7 @@ async def to_code(config: ConfigType) -> None:
 
     # ESP8266 and RP2040 inflate gzip at reboot; the rest inflate on the fly
     if not (CORE.is_esp8266 or CORE.is_rp2):
-        cg.add_define("USE_OTA_DEFLATE")
+        enable_deflate()
 
     # One key per device: an api encryption block supplies it (static or
     # runtime) and offers; the ota block only adds the requirement