Lewis County Post Office

Find Lewis County New York post offices and USPS mailing boxes. Post offices provide information on bulk mail services, domestic mail delivery, international shipping, change of address, mail forwarding, PO boxes, and passport services.


Beaver Falls Post Office 9572 Main Street Beaver Falls NY 13305 315-346-6412


Castorland Post Office 5158 Highway 410 Castorland NY 13620 315-376-0371

Constableville Post Office 3109 Main Street Constableville NY 13325 315-397-2375

Copenhagen Post Office 9886 Route 12 Copenhagen NY 13626 315-688-2920

Croghan Post Office 6915 Bank Street Croghan NY 13327 315-346-6012

Glenfield Post Office 6036 Main Street Glenfield NY 13343 315-376-6166

Harrisville Post Office 14220 State Street Harrisville NY 13648 315-543-2220

Lowville Post Office 7651 North State Street Lowville NY 13367 315-376-3111

Lyons Falls Post Office 3864 Fulton Street Lyons Falls NY 13368 315-348-8623

Martinsburg Post Office 5604 Whitaker Road Lowville NY 13367 315-376-5944

Port Leyden Post Office 7085 West Main Street Port Leyden NY 13433 315-348-6312

Turin Post Office 4205 Route 26 Turin NY 13473 315-348-8007

West Leyden Post Office 1054 Highway 26 West Leyden NY 13489 315-942-2081

What Change of Address options are available?

Customers can request a temporary or permanent Change of Address either online or in person at the Post Office using PS Form 3575. The online application for Change of Address has a $1.00 identity validation fee.

Is it possible to insure mail and items sent via the USPS?

Yes. Standard mail can be insured for up to $5,000 for an additional fee. Registered mail items can be insured for up to $50,000.

What is the USPS Office of Inspector General?

The Office of Inspector General (OIG) is a division within the USPS responsible for ensuring the integrity and accountability of the postal service. It conducts investigations to safeguard the postal system and performs audits and reviews.