If your order is being delivered by USPS, then a signature is not required.
Signatures are mandatory on all international FedEx shipments. This is part of the service offered by FedEx, and not something which we can waive. You can sign up for the FedEx Shipment Delivery Manager, where you can manage your deliveries with FedEx, which includes leaving a 'digital signature' on file so FedEx are able to leave packages in your absence, bypassing the chance of missing a delivery. Click here for further details about the FedEx Delivery Manager.
Learn more here.