24-Hour Rule

Carriers and NVOCCs must transmit manifest data electronically, including a precise cargo description, weight, shipper and consignee and container and seal numbers, at least 24 hours before loading. CBP may issue a do-not-load message for high-risk or incomplete filings. Statutory penalties under 19 U.S.C. 1436 are $5,000 for a first violation and $10,000 for each later one, adjusted for inflation, and late-filed cargo can be denied permission to unload. Bulk cargo and some break-bulk cargo are exempt.

The 24-hour rule sets an early checkpoint in the ocean import timeline: if a carrier lacks accurate cargo descriptions in time, the container misses the vessel. Vague descriptions such as general merchandise or consumer goods are rejected, so a brand's supplier must give specific product descriptions with the booking. For fulfillment planning, purchase order data needs to be final several days before departure, along with the importer's ISF, or inventory arrives a week or more late.

• Importer Security FilingISFOcean import filing due before loading
• Ocean Bill of LadingOcean carrier's receipt and contract

• Container Security Initiative (CSI)2002 · US officers screen containers at foreign ports
• September 11 Attacks and Supply Chain Security2001 · Border closures halt parts and cargo security tightens

• Trade Act of 20022002 · US law mandating advance electronic cargo data
• SAFE Port Act of 20062006 · Port security law behind C-TPAT and the ISF rule
• WCO SAFE Framework of Standards2005, latest edition 2025 · WCO standards for supply chain security and AEO programs

1. 19 CFR 4.7, Inward foreign manifest; advance cargo information law.cornell.edu
2. 19 U.S.C. 1436, Penalties for violations of arrival, reporting, entry and clearance requirements law.cornell.edu