diff --git a/esphome/components/api/api_connection.h b/esphome/components/api/api_connection.h
index d47423b517..15d79a25ec 100644
--- a/esphome/components/api/api_connection.h
+++ b/esphome/components/api/api_connection.h
@@ -23,10 +23,7 @@ static constexpr uint32_t KEEPALIVE_TIMEOUT_MS = 60000;
 // TODO: Remove MAX_INITIAL_PER_BATCH_LEGACY before 2026.7.0 - all clients should support API 1.14 by then
 static constexpr size_t MAX_INITIAL_PER_BATCH_LEGACY = 24;  // For clients < API 1.14 (includes object_id)
 static constexpr size_t MAX_INITIAL_PER_BATCH = 34;         // For clients >= API 1.14 (no object_id)
-// Maximum number of messages to process in a single batch
-// This limit exists to prevent stack overflow from the MessageInfo/iovec arrays in process_batch_
-// Each MessageInfo is 6 bytes, each iovec is 8 bytes: 34 * (6 + 8) = 476 bytes
-static constexpr size_t MAX_MESSAGES_PER_BATCH = 34;
+// Verify MAX_MESSAGES_PER_BATCH (defined in api_frame_helper.h) can hold the initial batch
 static_assert(MAX_MESSAGES_PER_BATCH >= MAX_INITIAL_PER_BATCH,
               "MAX_MESSAGES_PER_BATCH must be >= MAX_INITIAL_PER_BATCH");
 
diff --git a/esphome/components/api/api_frame_helper.h b/esphome/components/api/api_frame_helper.h
index 07997ac7a0..76a93d094e 100644
--- a/esphome/components/api/api_frame_helper.h
+++ b/esphome/components/api/api_frame_helper.h
@@ -29,6 +29,10 @@ static constexpr uint16_t MAX_MESSAGE_SIZE = 8192;  // 8 KiB for ESP8266
 static constexpr uint16_t MAX_MESSAGE_SIZE = 32768;  // 32 KiB for ESP32 and other platforms
 #endif
 
+// Maximum number of messages to batch in a single write operation
+// Must be >= MAX_INITIAL_PER_BATCH in api_connection.h (enforced by static_assert there)
+static constexpr size_t MAX_MESSAGES_PER_BATCH = 34;
+
 class ProtoWriteBuffer;
 
 // Max client name length (e.g., "Home Assistant 2026.1.0.dev0" = 28 chars)