What Is a Steel Split in Customs? A Complete Guide to Section 232 Entry Splits
Steel splits are one of the most tedious parts of filing a customs entry. If you are new to brokerage or just trying to understand what they are, this guide walks through the mechanics, the math, and the common pitfalls.
If you have ever looked at a customs entry for imported machinery, auto parts, or industrial equipment, you may have noticed that a single product sometimes appears as two separate line items on the 7501 entry summary. That is a steel split, and it exists because of Section 232 tariffs on steel imports.
Steel splits are not optional. They are a CBP requirement, and getting them wrong can lead to duty underpayments, penalties, or delays. For customs brokers, they represent some of the most time-consuming manual work in entry filing.
What Exactly Is a Steel Split?
A steel split is the process of separating the steel component of an imported product from its non-steel component on a customs entry. When you import a product that contains steel, the steel portion must be reported on its own entry line so that Section 232 duties can be assessed against it specifically.
For example, imagine you are importing an industrial pump that is 60% steel by value and 40% other materials (rubber seals, copper wiring, plastic housing). Instead of entering that pump as a single line item, you must split it into two lines:
- Line 1: The steel component (60% of the value), classified under the product's normal HTS code plus a Chapter 99 secondary tariff code for Section 232
- Line 2: The non-steel component (40% of the value), classified under the product's normal HTS code with no 232 surcharge
Both lines reference the same product on the same invoice. The split is purely for tariff assessment purposes.
Why Steel Splits Exist: Section 232 Tariffs
Steel splits are a direct consequence of the Section 232 tariffs imposed starting in 2018. Under Section 232 of the Trade Expansion Act of 1962, the U.S. government can impose tariffs on imports deemed a threat to national security. The investigation concluded that steel and aluminum imports threatened to impair national security by undermining domestic production capacity.
The resulting tariffs are:
- 25% on steel articles and products containing steel
- 10% on aluminum articles and products containing aluminum
The key phrase is "products containing steel." The tariff does not only apply to raw steel coils or steel bars. It applies to the steel content within finished and semi-finished goods. That is why a broker cannot simply enter an industrial pump as one line item and pay the normal duty rate. The steel inside that pump is subject to the 25% surcharge, and CBP requires it to be broken out.
Important distinction: Not all steel-containing products require a split. Products classified under HTS chapters that are explicitly covered by Section 232 (primarily chapters 72 and 73) may already carry the 232 duty on the full value. Steel splits are most common for products in other chapters where steel is a component but not the defining material of the classification.
How Steel Splits Work Mechanically
The mechanics of a steel split involve taking a single commercial invoice line item and creating two entry summary lines from it. Here is how the process works step by step.
Step 1: Determine Steel Content
The importer or their supplier provides the steel percentage for each product, usually as a percentage of value, weight, or both. Some importers provide a per-piece steel value and steel weight. This information typically comes from a bill of materials or a manufacturer declaration.
Step 2: Prorate Value and Weight
Using the steel percentage, the broker splits the total entered value and net weight of the line item into steel and non-steel portions.
Example Calculation
A shipment of 500 brackets at $12.00 each. Steel content is 70% by value.
FieldSteel LineNon-Steel LineQuantity500500Unit Value$8.40 (70%)$3.60 (30%)Total Value$4,200.00$1,800.00Net WeightProrated to steel %Prorated to non-steel %HTS CodePrimary HTS + 9903.80.01Primary HTS only
The $4,200 steel portion is then subject to the 25% Section 232 duty on top of any normal duty rate.
Step 3: Apply the Correct Chapter 99 Code
The steel line item must carry a Chapter 99 secondary classification. The two most common codes are:
- 9903.80.01 - Steel articles from countries subject to standard Section 232 tariffs (25%)
- 9903.80.02 - Steel articles where the melt-and-pour country differs from the country of export, or where specific country-based provisions apply
Choosing the correct code depends on the country of origin, the country where the steel was melted and poured, and any applicable exclusions or quotas. Getting this wrong is one of the more consequential errors a broker can make. For a deeper look at how these tariff provisions work, see our Section 232 tariff guide.
AD/CVD Complications
Steel splits become even more complex when the steel component is also subject to antidumping (AD) or countervailing duty (CVD) orders. Many steel products from specific countries carry AD/CVD rates that stack on top of the Section 232 tariff.
In practice, this means the steel line from your split may carry:
- The normal column 1 duty rate for the HTS classification
- The 25% Section 232 surcharge
- An AD duty rate (sometimes over 100% for certain countries and products)
- A CVD rate on top of everything else
Brokers need to check whether the steel type and country of origin fall under any active AD/CVD order. The combination of a steel split plus AD/CVD reporting on the same line item is one of the most error-prone areas in customs entry work.
Why Steel Splits Are Painful for Brokers
In theory, a steel split is straightforward math. In practice, it is one of the most tedious tasks in customs brokerage. Here is why:
- Volume: A single entry might have 50, 100, or even 300+ line items. Each one that contains steel needs to be split, effectively doubling the line count.
- Varying percentages: Different parts on the same entry may have different steel percentages. Part A might be 85% steel, Part B might be 30%, and Part C might have no steel at all. The broker has to track and apply the correct percentage for each.
- Weight and value proration: Both gross weight and entered value must be prorated accurately. Rounding errors compound across hundreds of lines and can cause the entry totals to not reconcile with the invoice.
- Reference data management: Steel percentages come from the importer, often in separate spreadsheets or specification documents. Matching part numbers from the invoice to the correct steel data is manual and error-prone.
- Changing data: Importers update their product mix, change suppliers, or revise steel percentages. Brokers have to keep their reference data current.
Common Mistakes
After working with customs brokers across the industry, these are the errors that come up most frequently with steel splits:
- Forgetting to split entirely: A new part gets added to an order that contains steel, but the broker does not have it in their reference data. The entry goes through without the 232 duty assessed, creating a potential underpayment.
- Wrong steel percentages: Using outdated percentages or applying the wrong percentage to a part number. Even a small percentage error, multiplied across thousands of units, produces a meaningful duty discrepancy.
- Incorrect Chapter 99 code: Applying 9903.80.01 when the melt-and-pour country requires 9903.80.02, or vice versa. This can trigger CBP rejections or post-entry audits.
- Math errors in proration: Rounding issues, transposed values, or formula mistakes in the spreadsheet. When the prorated values do not add up to the invoice total, the entry will not balance.
- Missing AD/CVD flags: Splitting the steel correctly but failing to add the required AD/CVD case number and deposit rate to the steel line.
How Brokers Handle Steel Splits Today
The current standard workflow for most brokerages is manual and spreadsheet-driven:
- Receive the commercial invoice with part numbers, quantities, and values.
- Cross-reference each part number against a steel percentage reference document (usually an Excel file maintained per importer account).
- Calculate the split for each line item: multiply value and weight by the steel percentage for the steel line, and by the inverse for the non-steel line.
- Create two entry lines per split item in the brokerage software, manually entering the prorated values, weights, and the Chapter 99 code on the steel line.
- Reconcile totals to make sure the sum of all split lines equals the invoice totals.
For a simple entry with 10 line items, this might take 15 minutes. For a complex entry with 200+ lines and varying steel percentages, it can take hours. Multiply that across dozens of entries per day and the labor cost becomes substantial. It is also exactly the kind of repetitive, rules-based work where human fatigue leads to mistakes.
A Better Approach
Steel splits follow clear, deterministic rules: look up the steel percentage, multiply, create two lines, apply the right tariff code. That makes them a natural candidate for automation. The challenge has been that most brokerage software does not handle the split logic natively, so brokers have been stuck with spreadsheets.
Newer tools are starting to change this. By mapping importer part numbers to their steel content data and applying the proration logic automatically, brokers can eliminate the manual calculation step entirely and reduce the error rate to near zero.
Tired of Manual Steel Splits?
Cervo automates steel split calculations, Chapter 99 code assignment, and value/weight proration across your entire entry. Brokers using Cervo complete steel-split entries in minutes instead of hours.
