A customs bond is the first thing a new commercial importer has to buy. It is not insurance for your cargo — it is a guarantee to U.S. Customs and Border Protection that the duties, taxes and penalties on your entry will be paid. CBP will not release a commercial shipment without one, and the bond has to be on file **before the goods arrive**, not after the vessel docks. There are two shapes. A **single-entry bond** covers one shipment and is priced off the value plus duty of that shipment. A **continuous bond** covers every entry you file nationwide for a year, is priced off your annual duty, and renews automatically. The usual rule of thumb: if you import more than about three or four times a year, the continuous bond costs less than the single-entry bonds it replaces, and it also covers the ISF filing that a single-entry bond does not. The companies listed here are the sureties themselves — the ones whose name and whose money actually stand behind the bond. Treasury lists them annually in Department Circular 570 under 31 CFR 223, and CBP assigns most of them a 3-digit surety code that appears on the bond. **Two honest caveats.** Most of these companies are large general insurance and casualty carriers, not customs specialists; a customs bond is a small line of business next to their construction and contract surety books. And most importers never contact them directly — you buy the bond **through your customs broker**, or through a bond agent writing on the surety's behalf, and the broker handles the application and the CBP filing. Use this list to check that the surety behind a bond you have been quoted is genuinely Treasury-certified, and to see how much bond that company is authorised to write.