Clue: Mail delivery org.

Answer: USPS

Length: 4

---

Similar Clues:

• Organizes, as mail (SORTS with 5 letters)
• Mail delivery rental (POBOX with 5 letters)
• Rural mail delivery services, once (RFDS with 4 letters)
• Mail delivery paths: Abbr. (RTES with 4 letters)
• Mail delivery, to Brits (POST with 4 letters)
• Mail delivery assignments: Abbr. (RTES with 4 letters)
• 19th-century mail delivery service (PONYEXPRESS with 11 letters)
• Organizes the mail (SORTS with 5 letters)
• Outlying mail delivery svc. (RFD with 3 letters)
• Some mail rtes. (RFDS with 4 letters)