Mailing and hand carry addresses

The USPTO encourages customers to take advantage of the efficiency and convenience of our online business systems; however, you may also conduct official correspondence with us via post mail and hand delivery. 

For most correspondence (e.g., new patent applications) no mail stop is required because the processing of the correspondence is routine. If NO mail stop is included on the list below, no mail stop is required for the correspondence. Only the specified type of document should be placed in an envelope addressed to one of these special mail stops. If any documents other than the specified type identified for each special mail stop are addressed to that mail stop, they will be significantly delayed in reaching the appropriate area for which they are intended. The mail stop should generally appear as the first line in the address.