# Esun Order Number

Generates order increment IDs from one atomic sequence per Magento Website.

Configure **Stores > Configuration > Esun > Order Number** after
switching the configuration scope to the target Website. The generated format
is `Site Name` + `Number`, for example `US100001`.

`First Order Number` initializes a Website only when its first order number is
reserved. It deliberately does not reset a sequence that has already started.
Invoice, shipment and credit memo sequences are unchanged.