A 0% rate is not a free import
6 min read · updated 2026-11-12
Search any electronics heading on this site and most lines will read “Free”. That is the general rate — the HTS column. It is not the bill. Several charges are applied outside the tariff schedule, and none of them appear in the three rate columns.
1. Merchandise Processing Fee (MPF)
An ad valorem fee of 0.3464% of the entered value, with a floor and a ceiling that are reset each fiscal year. Formal entries pay it; informal entries under the threshold pay a flat amount instead.
On a $50,000 shipment that is roughly $173 — small, but it is charged whether the duty rate is 0% or 30%. It is also why very small formal entries are disproportionately expensive: the floor is a fixed cost that a $900 shipment cannot amortise.
2. Harbor Maintenance Fee (HMF)
0.125% of value on commercial cargo moved through US ports by vessel. Air and land shipments do not pay it. Like MPF, it applies on top of a zero duty rate.
3. Section 301 and Section 232 duties
Section 301 duties are imposed on specified Chinese-origin goods and are listed in Chapter 99 of the HTS, not in the rate columns of the regular chapters. A line can read “Free” in Chapter 84 and still carry a substantial additional duty because the product appears on a Chapter 99 list.
Section 232 covers national-security measures on specific product categories — steel, aluminium and their derivatives being the longest-running example. These are also layered on top.
4. Antidumping and countervailing duties
AD/CVD is case-specific: an order names a product and a country, and the rate can be punitive — often well above 100%. It is assessed under a separate case number, requires a cash deposit at entry, and is not visible in the HTS at all. If an order covers your product, the HTS rate is almost irrelevant to the economics.
5. Quota and licensing
Some lines carry tariff-rate quotas: a lower rate inside the quota, a much higher one outside. Others need a visa, permit or PGA (partner government agency) message before CBP will release the goods. Neither changes the printed rate, and both can stop a shipment that looked duty-free.
Worked example
A $100,000 ocean shipment of goods on a Free general-rate line, no Section 301, no AD/CVD:
| Charge | Basis | Amount |
|---|---|---|
| Duty | 0% general rate | $0 |
| MPF | 0.3464% of value | $346.40 |
| HMF | 0.125% of value | $125.00 |
| Total at border | $471.40 |
Add a 25% Section 301 duty and the same shipment costs $25,471.40 instead. The HTS rate did not change. Only the part of the bill you were not looking at did.
What to do with this
- Use the HTS rate as the first input, never the final number.
- Check Chapter 99 for the specific product and country pair.
- Ask your broker for the AD/CVD case status in writing before you commit to a price.
- Build MPF and HMF into landed cost even when duty is zero — they are the reason small shipments lose money.