USPS Postmark Changes Affect Unclaimed Property & Retirement Plan Compliance

Historically, individuals and businesses in the United States have relied on postmarks to provide an official record of the date and location that letters and packages were accepted by the U.S. Postal Service. When filing tax returns, voting by mail, and conducting other business that requires action by specific deadlines, postmarks have served as legal proof of compliance. A new USPS Postmarks and Postal Possession rule, implemented on Dec. 24, 2025, is disrupting this long-standing reliance on postmarks, and the ripple effects extend to numerous legal requirements, including unclaimed property compliance and retirement plan outreach.

Because property holders often rely on mail to maintain contact with property owners and for outreach when accounts become dormant, changes to mail handling policies and practices can significantly affect the timing and effectiveness of unclaimed property procedures. Similarly, entities with retirement program fiduciary duties may rely on mail to solicit Required Minimum Distribution applications, notify plan participants of age of commencement and other essential communications.

According to the USPS, postmark practices haven’t changed. Rather, the new rule aims to improve understanding of postmarks and their relationship to the mailing date: “While the presence of a postmark on a mailpiece confirms that the Postal Service was in possession of the mailpiece on the date of the postmark’s inscription, the postmark date does not inherently or necessarily align with the date on which the Postal Service first accepted possession of the mailpiece.”

This misalignment between USPS possession and the postmark date is expected to become more common as the agency implements its Regional Transportation Optimization initiative. Under RTO, mail dropped at post offices and collection boxes more than 50 miles from a USPS regional hub is collected the next day rather than the same day. The number of days for mail to be delivered after it is dropped may be longer than usual, depending on the drop location. Rural areas are especially likely to be affected.

In the world of unclaimed property compliance, property holders are responsible for complying with state due diligence requirements tied to specific mailing deadlines. Depending on the applicable state’s requirements, holders generally must send a first-class letter to owners of dormant property between 60 and 180 days before the reporting deadline, notifying them that the property will be escheated to the state if the owner does not promptly respond.  The same can be said for retirement plans that have several areas where a postmark can make the difference between compliance or failure.

Some states, including New Jersey, New York and Ohio, require the use of certified mail and return receipts for accounts over specified value thresholds and these types of requirements are mirrored in the guidance from the DOL for retirement plans in certain scenarios. Certified mail is handled differently from first-class mail and provides a dated mailing receipt indicating when the USPS first handled the letter. However, lower-value accounts and mailings for states and regular mailings from a retirement plan without such requirements typically require only first-class mail and therefore depend on a postmark.

Postmarks may be used as evidence of compliance or non-compliance with these due diligence or required deadlines, which is why the new USPS rule and RTO practices affect holders and plan sponsors. The USPS offers a few solutions for anyone needing to meet specific mailing deadlines:

• Send mailings earlier.
• Request a manual (local) postmark at a retail location at no additional cost.
• Purchasing a Certificate of Mailing.
• Use Registered Mail or Certified Mail services, which provide mailing receipts for individual mailpieces.

Implementing and following best practices for responsibilities such as unclaimed property due diligence and retirement plan outreach can be daunting. Fortunately, MarketSphere’s experts are available to relieve the burden. For help with your compliance needs, contact us to learn more and get started.

*Content contained in this article is considered accurate as of the publish date.