Analysis
HTS 2509.00.20 covers chalk: other under heading 2509 (chalk).
The normal trade relations rate here is zero, shared by about 91% of the 78 tariff lines in chapter 25, a useful check when a neighbouring dutiable line is a candidate. Free here means free of the base duty only: origin-specific Chapter 99 duties such as Section 301 can still be owed.
The other line in the same group is 2509.00.10 (chalk: crude, duty-free).
Census statistics map these goods to NAICS 212312 (Crushed and Broken Limestone Mining and Quarrying), an industry of 1,376 US establishments employing 25,735 people. That concordance is how imports of this line are compared with US output.
Goods from countries without normal trade relations pay the column 2 rate of 13% instead of nothing, so origin decides between free entry and a 13% duty.
Every edition we compared, from Jan 2023 to Oct 2026 (Rev. 22), shows the same general rate of Free.
Neighbouring lines
| Line | Description | General rate |
|---|---|---|
| 2509.00.10 | Chalk: crude | Free |