If you need to apply using the postal option, this is the address to send the passports to the EU Settlement Scheme.

EU Settlement Scheme
PO Box 2075
Liverpool
L69 3PG

Make sure you write the application number on the front of the envelope.

The Post Office recommends using the Special Delivery service (Guaranteed Next Day) to send important documents such as passports, as opposed to just the signed for service.

Documents are usually returned within 3 days excluding transit time, as noted here: EU Settlement Scheme: current estimated processing times for applications - GOV.UK

Time taken to return documents

If you post your identity document to us, it is usually returned within 3 days of being received. This does not include the time your document is in transit. If you plan to travel soon, you should wait until you return before sending us any documents you require for travel.