diff --git a/esphome/components/api/api_pb2.cpp b/esphome/components/api/api_pb2.cpp
index a33604e665..6db5dcf97e 100644
--- a/esphome/components/api/api_pb2.cpp
+++ b/esphome/components/api/api_pb2.cpp
@@ -2334,7 +2334,6 @@ uint8_t *BluetoothLERawAdvertisementsResponse::encode(ProtoWriteBuffer &buffer P
     auto &sub_msg = this->advertisements[i];
     ProtoEncode::write_raw_byte(pos PROTO_ENCODE_DEBUG_ARG, 10);
     uint8_t *len_pos = pos++;
-    uint8_t *body_start = pos;
     ProtoEncode::write_raw_byte(pos PROTO_ENCODE_DEBUG_ARG, 8);
     ProtoEncode::encode_varint_raw_64(pos PROTO_ENCODE_DEBUG_ARG, sub_msg.address);
     ProtoEncode::write_raw_byte(pos PROTO_ENCODE_DEBUG_ARG, 16);
@@ -2346,7 +2345,7 @@ uint8_t *BluetoothLERawAdvertisementsResponse::encode(ProtoWriteBuffer &buffer P
     ProtoEncode::write_raw_byte(pos PROTO_ENCODE_DEBUG_ARG, 34);
     ProtoEncode::write_raw_byte(pos PROTO_ENCODE_DEBUG_ARG, static_cast<uint8_t>(sub_msg.data_len));
     ProtoEncode::encode_raw(pos PROTO_ENCODE_DEBUG_ARG, sub_msg.data, sub_msg.data_len);
-    *len_pos = static_cast<uint8_t>(pos - body_start);
+    *len_pos = static_cast<uint8_t>(pos - len_pos - 1);
   }
   return pos;
 }
diff --git a/script/api_protobuf/api_protobuf.py b/script/api_protobuf/api_protobuf.py
index e5b3f773e7..6f92e4cb6d 100755
--- a/script/api_protobuf/api_protobuf.py
+++ b/script/api_protobuf/api_protobuf.py
@@ -1596,7 +1596,6 @@ def _generate_inline_encode_block(
     lines.append(f"auto &sub_msg = {element};")
     lines.append(f"ProtoEncode::write_raw_byte(pos, {tag});")
     lines.append("uint8_t *len_pos = pos++;")
-    lines.append("uint8_t *body_start = pos;")
 
     # Generate inline field encoding for each sub-message field
     for field in sub_desc.field:
@@ -1608,7 +1607,7 @@ def _generate_inline_encode_block(
         encode_line = encode_line.replace("this->", "sub_msg.")
         lines.extend(encode_line.split("\n"))
 
-    lines.append("*len_pos = static_cast<uint8_t>(pos - body_start);")
+    lines.append("*len_pos = static_cast<uint8_t>(pos - len_pos - 1);")
     return "\n".join(lines)