> ## Documentation Index
> Fetch the complete documentation index at: https://hedera-0c6e0218-mintlify-bc559771.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# FileAppend

> FileAppendTransactionBody protobuf message used by the Hedera File Service to append additional contents onto the end of an existing file.

## FileAppendTransactionBody

‌Append the given contents to the end of the specified file. If a file is too big to create with a single FileCreateTransaction, then it can be created with the first part of its contents, and then appended as many times as necessary to create the entire file.

| Field      | Type                                               | Description                                                      |
| ---------- | -------------------------------------------------- | ---------------------------------------------------------------- |
| `fileID`   | ​[FileID](/reference/protobuf/basic-types/fileid)​ | The file to which the bytes will be appended                     |
| `contents` | ​bytes                                             | The bytes that will be appended to the end of the specified file |