diff --git a/subsys/logging/backends/Kconfig.uart b/subsys/logging/backends/Kconfig.uart
index 5cb89a1ec8f..43b544ab66a 100644
--- a/subsys/logging/backends/Kconfig.uart
+++ b/subsys/logging/backends/Kconfig.uart
@@ -17,12 +17,16 @@ config LOG_BACKEND_UART_ASYNC
 	depends on !LOG_BACKEND_UART_OUTPUT_DICTIONARY_HEX
 
 config LOG_BACKEND_UART_BUFFER_SIZE
-	int "Number of bytes to buffer in RAM before flushing"
+	int "Maximum number of bytes to buffer in RAM before flushing"
 	default 32 if LOG_BACKEND_UART_ASYNC
 	default 1
 	help
-	  Sets the number of bytes which can be buffered in RAM before log_output_flush
-	  is automatically called on the backend.
+	  In deferred logging mode, sets the maximum number of bytes which can be buffered in
+	  RAM before log_output_flush is automatically called on the UART backend.  The buffer
+	  will also be flushed after each log message.
+
+	  In immediate logging mode, processed log messages are not buffered and are always
+	  output one byte at a time.
 
 config LOG_BACKEND_UART_AUTOSTART
 	bool "Automatically start UART backend"