With the files feature, Xero gives users the ability to attach documents to bills. When a document is attached to the bill, it can be referenced with a single click.
Next, click on “+Upload files…” A window to the files on your computer will open. Simply point to where you saved the document that you are trying to attach. Click Open.
After the document is attached, a number will appear next to the files icon indicating how many documents are attached to the bill.