(a)(1) Claims for benefits shall be delivered, mailed to, or presented at, any of the various district offices of the Social Security Administration, or any of the various offices of the Department of Labor authorized to accept claims, or, in the case of a claim filed by or on behalf of a claimant residing outside the United States, mailed or presented to any office maintained by the Foreign Service of the United States. A claim shall be considered filed on the day it is received by the office in which it is first filed.

(2) A claim submitted to a Foreign Service Office or any other agency or subdivision of the U.S. Government shall be forwarded to the Office and considered filed as of the date it was received at the Foreign Service Office or other governmental agency or unit.

(b) A claim submitted by mail shall be considered filed as of the date of delivery unless a loss or impairment of benefit rights would result, in which case a claim shall be considered filed as of the date of its postmark. In the absence of a legible postmark, other evidence may be used to establish the mailing date.