Customs Bonds for U.S. Importers: Continuous, Single Entry, ISF & TIB

The regulation itself is deliberately open-ended. 19 CFR 113.13 sets a statutory floor of just $100 for any CBP bond and directs CBP to size bonds using six discretionary factors: your duty payment record, prior compliance with CBP demands, the value and nature of your merchandise, the degree of CBP supervision required, your bond history, and the information in your application. Your continuous bond application must disclose the total duties, taxes, and fees you paid on all imports in the prior calendar year (19 CFR 113.11) — and that number is what CBP's sizing guidance keys off.

In practice, CBP's Monetary Guidelines apply that discretion through a formula: the standard Activity Code 1 continuous bond is set at 10% of the duties, taxes, and fees paid in the prior 12 months, rounded up, with a $50,000 minimum. An importer who paid $480,000 last year computes to $48,000 — which rounds up to the $50,000 floor. An importer who paid $800,000 needs an $80,000 bond. New importers with no history use projected duties for the coming year, subject to CBP review.

Single entry bonds are sized per shipment rather than per year. As a working rule, expect the bond to cover at least the entered value plus all duties, taxes, and fees, with substantially higher amounts for merchandise regulated by other agencies (FDA, USDA, DOT) or subject to quota — the single entry bond page works through real examples for vehicles, household goods, and one-off commercial purchases. The exact multiples are CBP administrative practice rather than codified regulation, so your customs broker or surety confirms the figure before the entry is filed.

The stakes for getting this right are written into the bond conditions: if duties go unpaid, the default assessment under 19 CFR 113.62(n) is two times the unpaid amount or $1,000, whichever is greater. The full regulatory text is at 19 CFR Part 113, and our customs bond requirements guide translates it into plain English.

The 10% formula has not changed — duty bills have. Since 2025, Section 232 steel and aluminum duties, Section 301 China-origin tariffs, and the post-2024 IEEPA reciprocal tariff layer have been stacking on the same shipments. Because the continuous bond is sized off your trailing 12-month duty total, every tariff increase passes straight through to bond sizing: an importer whose annual duties jump from $480,000 to $800,000 sees the required bond rise from the $50,000 floor to $80,000 at the next sufficiency check.

CBP runs those checks automatically in its ACE system. When your bond falls short, the regulation is specific about what happens next: under 19 CFR 113.13(c), CBP notifies you and your surety in writing and gives you 15 days to remedy the deficiency. If CBP decides the gap places revenue in jeopardy, 113.13(d) lets it demand immediate additional security — cash deposits or single transaction bonds on every entry — which is far more expensive than simply filing a bigger bond.

The practical move is to re-check your bond size before CBP does. Total your duties, taxes, and fees over the last 12 months (your broker's ACE reports have this), apply 10%, and compare it to your current penal sum. If you are over, replace the bond proactively — our continuous bond and reconciliation rider page covers the upgrade process, including the anti-dumping and countervailing duty scenarios where exposure multiplies fastest, and you can start a replacement bond quote with your new duty figure today.

Not everything that crosses the border is staying. Trade show booths, demo equipment, goods entering for repair, and commercial samples can enter duty-free under a temporary import bond (TIB) — the bond guarantees CBP that the goods will be exported instead of sold into the U.S. market. If they are not exported on time, the surety pays and then comes to you.

The alternative is an ATA Carnet, an international customs document that serves the same duty-free purpose across multiple countries on one document. The rough split: a carnet wins when the same goods tour several countries; a TIB wins for U.S.-only temporary entries, goods a carnet program does not cover, or when the carnet deadline has already been missed. The TIB page has the full eligibility list and process, and the TIB calculator estimates the bond amount from your goods' dutiable value.