US customs tax calculator: every charge CBP assesses at entry
Most pages that call themselves a customs tax calculator return one number - the tariff percentage - and leave you to discover the rest on the broker's invoice. This one starts from what actually happens at the port of entry: an entry is filed, CBP assesses duty on a classified line, adds any Chapter 99 surcharge that covers your origin, charges two fees for processing, and releases the goods. Enter a code and an origin below and the page resolves the official rate for that line, shows whether a surcharge stacks on top, and carries the same code into the dollar calculator.
Duty rates read from the official machine-readable US schedule (23,193 ten-digit lines, USITC export generated 2026-10-19); fees per the FY2027 schedule effective 2026-10-01.
Short answer: what people call the customs tax is the sum of the duty on the classified HTS line, any Chapter 99 surcharge (Section 301 for China origin, for example), the merchandise processing fee at 0.3464% with a $34.58 floor and a $670.86 ceiling, and the harbor maintenance fee at 0.125% on ocean cargo. Four facts set those amounts: classification, customs value, origin, entry type.
Four facts decide the bill, and only one of them is a rate
Classification is the fact people fixate on, because the rate is visible on it. But a rate is only as good as the line it belongs to, and the same product described two plausible ways can land on lines several percentage points apart - which is why CBP issues binding rulings and why a misclassification is corrected by a prior disclosure rather than a phone call. Our guide to the ten-digit suffix covers the specific trap of stopping at eight digits: siblings under one heading share a stem and often differ in rate.
Customs value is the base. For an ordinary US purchase it is transaction value: the price actually paid or payable, plus statutory additions such as assists, royalties that are a condition of sale, and the selling commission. Critically, the United States assesses on an FOB-like basis rather than CIF, so international freight and insurance stay out of the dutiable base. The FOB versus CIF guide works through the arithmetic on a single container, because importing the EU habit of quoting CIF inflates a US duty estimate by precisely the freight percentage.
Origin is the fact that decides the stack rather than the rate. The Column 1 general rate belongs to the line and is the same for every normal-trade-relations partner. What origin changes is (a) whether a Chapter 99 surcharge attaches - Section 301 applies to listed Chinese-origin goods, and the same line from Vietnam or Mexico usually carries no such layer - and (b) whether a preference program can zero the rate entirely. The Special column lists what programs grant, while eligibility rests on origin rules the documentation must prove, so check the FTA eligibility checker before you book a claim into a price.
Entry type decides how the fees are computed. A formal entry is filed on an entry summary with the merchandise processing fee calculated per summary line at 0.3464% clamped to its floor and ceiling; an informal entry clears without a bond and without that summary, and its charges are structured differently. On small shipments the entry type can change the cost more than the duty rate does.
The rates on four real lines, and what China origin adds
These are current schedule values, not illustrations. The Column 2 figure in the middle is the statutory non-NTR rate for goods that do not qualify for normal trade relations - it is not a hypothetical ceiling, and it is roughly ten times the Column 1 rate on most consumer lines.
| HTS line | Goods | Column 1 general | Column 2 | China origin: Section 301 and the all-in rate |
|---|---|---|---|---|
| 8517.62.00.20 | Switching and routing apparatus | Free | 35% | no Section 301 action on this line |
| 4202.92.08.05 | Of cotton (369) | 7% | 40% | 9903.88.03 +25% → 32% |
| 8544.42.90.90 | Other | 2.6% | 35% | 9903.88.03 +25% → 27.6% |
| 9503.00.00.13 | 3 to 12 years of age | Free | 70% | no Section 301 action on this line |
Source: USITC HTS machine-readable export (hts.usitc.gov, generated 2026-10-19) for the rate columns; Chapter 99 Section 301 actions for China origin (hts.usitc.gov, fetched 2026-10-16) for the surcharge.
What the two fee lines on the entry summary mean
The merchandise processing fee is cost recovery for processing a formal entry, charged at 0.3464% of value per entry summary line with a $34.58 minimum and a $670.86 maximum in FY2027. It applies to duty-free goods too, which is the part importers forget when they celebrate a 0% rate on electronics: the duty is genuinely zero and the fee is not. The harbor maintenance fee is a 0.125% charge on the value of commercial cargo unloaded at US ports, so it applies to ocean freight and not to air or truck arrivals; it has no floor and no cap, unlike the MPF.
| Shipment value | MPF at 0.3464% | MPF charged | Why | HMF at 0.125% | Fees on this entry |
|---|---|---|---|---|---|
| $2,500.00 | $8.66 | $34.58 | raised to the minimum | $3.12 | $37.70 |
| $20,000.00 | $69.28 | $69.28 | percentage applies | $25.00 | $94.28 |
| $250,000.00 | $866.00 | $670.86 | capped at the maximum | $312.50 | $983.36 |
Source: MPF schedule for FY2027 effective 2026-10-01 (19 CFR 24.23(b)(1)(i); FAST Act adjustment per 19 CFR 24.22(k), Federal Register 2026-15530, fetched 2026-10-16); HMF statute 26 U.S.C. 4461(b); implemented at 19 CFR 24.27, fetched 2026-10-16.
Read the floor row first: on a $34.58 shipment the fee is mostly minimum, not percentage. That is why a duty-free air shipment can still show a customs charge on the invoice, and why comparing two forwarders on "duty" alone tells you nothing about which entry will cost less.
Where a customs tax estimate stops being trustworthy
- Antidumping and countervailing orders. These are not tariff lines. They are scope-specific orders with company-specific cash deposit rates, and a covered product can be assessed at a multiple of its Column 1 rate. Screen the code and origin with the AD/CVD screener before you quote a price that assumes the schedule rate.
- Classification disputes in progress. If a ruling or a protest is open on the line you use, the rate on the page is the rate CBP will apply today, not necessarily the rate that survives.
- Valuation adjustments discovered later. Assists, rebates, transfer pricing between related parties, and post-importation adjustments all move the base after the entry is filed and can produce a bill months later.
- Merchandise that needs another agency first. FDA, USDA, EPA, FCC and CPSC requirements can stop a release regardless of the duty calculation, and the cost of that delay never appears in a tax estimate.
Reading the output in the right order
Take the rate and the line from this page; take the value from your commercial invoice, on a transaction-value basis; take the origin from the documentation that will actually support an origin claim, not from where the goods shipped from; then decide the entry type with your broker. Multiply, add the surcharge for the origin you selected, add the two fees, and you have the number the entry summary should reconcile to. When you want that in dollars with the full Chapter 99 stack rather than percentages, the code and origin carry into the duty calculator without retyping.
Related calculators on this site
If you want the top-line total rather than the determination chain, the import tax calculator stacks the Chapter 99 layer and the entry fees onto the duty in a single number. If you only need the federal fees - the merchandise processing fee and the harbor maintenance fee - the import fee calculator isolates them and prices them at real shipment values.
Sources
Rate columns: USITC Harmonized Tariff Schedule machine-readable export (hts.usitc.gov, generated 2026-10-19), the dataset behind our HS code browser. Chapter 99 Section 301 actions: current Chapter 99 release fetched 2026-10-16. Merchandise processing fee: 19 CFR 24.23(b)(1)(i); FAST Act adjustment per 19 CFR 24.22(k) for FY2027, effective 2026-10-01, Federal Register 2026-15530. Harbor maintenance fee: 26 U.S.C. 4461(b); implemented at 19 CFR 24.27. All figures are recomputed at build time from those files.
Questions importers ask about the customs calculation
- What is a customs tax calculator actually computing?
- It computes what US Customs and Border Protection assesses on an entry: the duty on the classified tariff line, any Chapter 99 surcharge attached to that line and origin, the merchandise processing fee and the harbor maintenance fee. It does not compute freight, insurance, brokerage or state sales tax, because none of those are assessed by CBP at the port.
- Which four facts decide what CBP charges?
- Classification, customs value, origin and entry type. Classification picks the tariff line and therefore the rate. Customs value is the base the percentage is applied to. Origin decides whether a Chapter 99 surcharge or a preference program applies. Entry type decides whether you file a formal entry summary with its merchandise processing fee, or clear under an informal entry with a flat fee instead.
- What is the difference between Column 1 and Column 2 rates?
- Column 1 general is the normal most-favoured-nation rate that applies to goods from WTO members without a preference claim. Column 2 is the statutory non-NTR rate that applies to goods from countries without normal trade relations, and it is far higher on most lines - 33 1/3 percent against 8 percent, or 80 percent against 3.4 percent on the examples in this page. Column 2 is a real rate, not a theoretical ceiling.
- Is duty charged on the CIF or the FOB value in the United States?
- The United States assesses duty on a transaction-value basis, which behaves like FOB: the price paid or payable for the goods plus the additions required by statute, without international freight and insurance. The EU, the UK and most other markets assess on CIF. That single difference means the same invoice produces a smaller dutiable base in the United States than in Europe, and copying a CIF total into a US estimate overstates duty.
- When does an informal entry apply instead of a formal one?
- CBP allows informal entry for shipments of merchandise valued at or below the informal entry limit, and for certain other categories, and it is cleared without a bond and without the formal entry summary. If your shipment clears informally, the merchandise processing fee calculation changes and the entry will not look like the formal summary most calculators model. Check the current CBP threshold before assuming either path.
- Why does the customs tax differ from what my forwarder quoted?
- Three usual reasons, in order of frequency: the forwarder quoted duty only and left out the merchandise processing fee floor and the harbor maintenance fee; the classification used for the quote differs from the one filed on the entry; or a Chapter 99 layer such as Section 301 applies to your origin and production batch but was not in the quoting tool. Reconcile the entry summary line by line rather than the total.