Lawyers and businesspeople have long taken for granted the fact that a piece of mail deposited in an official mailbox or dropped off at a post office prior to mailing cut off time will receive a postmark that same date.
Effective as of the last few days of December 2025, that might no longer be true. It sounds inconsequential, but it could be anything but. That change has significant implications for contract notice provisions as well as for contractual compliance.
The key point is this. Postmarks are generally applied not when mail is collected from a mailbox or even at the retail counter, but at the first processing facility. Due to changes in transportation and processing logistics, some mail may not reach the first processing facility until a day or more after it is collected.
The Postal Service points out there’s been no change in their rules, that a postmark has always reflected the date of first processing, not the date of possession.
But that’s playing it a bit cute. In the past, the date of possession and the date of first processing were almost always the same. And now, they are not. There is now a significant chance that there is going to be a delay, perhaps of several business days, between the date a piece of mail is delivered to the post office, even handed directly to a postal clerk, and the date on which it is first processed, on which date it will receive a postmark.
I know this sounds a bit picky, or even crazy, so why does it matter? Because it has real world consequences in that many contracts provide that notice is effective “upon mailing,” or require that notice be “postmarked by” a specific deadline. Under those provisions, a party could deposit a notice on time, in good faith, and still end up with a postmark that makes the date of “mailing” appear late. That creates uncertainty, and uncertainty is the seed of disputes. And, what if the parties intended, or a court finds that they intended, that the term “date of mailing” means “date of postmark”?
This does not mean that every such notice is suddenly ineffective, nor does it resolve how a court would rule in any given case. But it does mean that reliance on a postmark as definitive proof of timeliness is now riskier than many assume.
There are practical steps to reduce that risk. For time-sensitive notices, parties can request a manual postmark at a USPS retail counter, use certified or registered mail, or obtain a certificate of mailing, each of which provides contemporaneous evidence of USPS acceptance. Redundant delivery methods, such as permitted email notice or courier service, can also help.
Although those steps might be sufficient, if they are remembered, the better practice is to immediately revisit all contractual notice and performance date provisions.
Clauses that hinge exclusively on postmarks might no longer reflect operational reality. Clear drafting, defining notice by receipt, or by documented acceptance rather than processing, or by avoiding, to the extent possible, Postal Service delivery as qualifying (which might not be possible depending on the application) can avoid unnecessary fights over a date stamp that might no longer mean what we once thought it did.
