US-Assembled Car Loan Tax Deduction

To deduct car loan interest under the new federal rule, the specific vehicle you financed must have undergone final assembly in the United States. You can prove it two ways the IRS accepts: the plant of manufacture encoded in the 11th character of the VIN (decoded free on NHTSA's site), or the "Final Assembly Point" on the window sticker. The brand's nationality, the dealer's location, and the share of US parts do not matter.

This page covers only the assembly test. For the $10,000 cap, the loan and refinancing rules, and the income phase-out, see the car loan interest deduction guide. Once you have confirmed assembly, the car loan interest deduction calculator estimates what the deduction is worth.

What "final assembly" means in the law

The statute, 26 U.S.C. §163(h)(4)(E)(i), defines final assembly as the process by which a manufacturer produces a vehicle at a plant or facility from which the vehicle is delivered to a dealer with all component parts necessary for mechanical operation included, whether or not they are permanently installed. A vehicle whose final assembly did not occur in the United States is not an "applicable passenger vehicle," and interest on its loan is not deductible.

Three things follow from that definition:

• It is a per-vehicle test. Two vehicles with the same make, model, and trim can have different answers.
• Parts origin is irrelevant. A vehicle can have mostly imported parts and still qualify, or mostly US parts and still fail.
• Engine and transmission origin are irrelevant. The window sticker lists them, but the deduction ignores them.

In the final regulations published on September 8, 2026 (TD 10054), Treasury rejected requests to decide assembly at the make-and-model level or to exempt vehicles from large US manufacturers, explaining that the same model can be assembled in different countries and the statute looks at the individual vehicle.

The two methods the IRS accepts

Treasury Regulation §1.163-16(e)(3) says you may rely on either:

1. The vehicle's plant of manufacture as reported in the VIN under 49 CFR Part 565; or
2. The final assembly point reported on the label affixed to the vehicle under 49 CFR 583.5(a)(3) — the parts-content section of the window sticker.

The final rules call the VIN decoder one non-exclusive, convenience option. If the decoder site is down, the window sticker works on its own.

How to read a VIN for the assembly test

Every VIN has 17 characters arranged in four sections under 49 CFR 565.15:

Why the first character is not enough

The first character of most VINs reflects the region where the manufacturer identifier was assigned. In practice, US-built vehicles usually start with 1, 4, or 5; Canadian-built vehicles with 2; and Mexican-built vehicles with 3. That pattern is a useful first glance, but the regulation points to the plant of manufacture, which is the 11th character. The plant letter means nothing by itself — "K" for one manufacturer and "K" for another are different factories — so you need the manufacturer's own decoding, which NHTSA publishes.

Step by step: using the NHTSA VIN decoder

1. Find the VIN. It appears at the base of the windshield on the driver's side, on the driver's door-jamb label, on the window sticker, and on your purchase contract and title.
2. Open the decoder. Go to NHTSA's vPIC VIN decoder and enter all 17 characters. Pick the model year if prompted.
3. Find the plant fields. In the results, look for Plant Country, Plant State, and Plant City. "UNITED STATES (USA)" in Plant Country satisfies the test.
4. Check the body and weight fields while you are there. Body Class and Vehicle Type confirm it is a car, SUV, minivan, van, pickup, or motorcycle, and GVWR shows a weight class that should be below 14,000 lb.
5. Save the result. Print or screenshot the page with the VIN visible and keep it with your tax records.

If the decoder returns "Incomplete VIN" or a check-digit error, re-read the VIN. The letters I, O, and Q are never used, so a "0" that looks like an "O" is always a zero.

Real decoder results: same brand, different answers

We ran VIN patterns for 2025 model-year vehicles through NHTSA's decoder in October 2026. Each pattern shows the first 11 characters with the check digit (position 9) replaced by "?" and the serial number omitted; position 10 ("S") is the 2025 model year and position 11 is the plant code. These are examples of how the output reads, not endorsements or a complete list.

Three lessons stand out. The RAV4 rows show one model name passing or failing depending on the plant, which is exactly why Treasury refused a model-level rule. The BMW and Kia Telluride rows show foreign brands that pass. The Ford Maverick row shows a US brand that fails.

Reading the window sticker instead

New passenger vehicles sold in the US carry a parts-content label required by the American Automobile Labeling Act, usually printed as a boxed section of the window sticker headed "PARTS CONTENT INFORMATION." Under 49 CFR 583.5, it shows:

• U.S./Canadian Parts Content: a percentage for the whole carline (ignore it for this test);
• Major Sources of Foreign Parts Content: up to two countries and percentages (ignore);
• Final Assembly Point: city, state, and country for this vehicle — this is the line that matters;
• Country of Origin — Engine and Transmission (ignore).

A label that reads "Final Assembly Point: Georgetown, Kentucky, U.S.A." satisfies the test. One that reads "Cambridge, Ontario, Canada" does not, even if US/Canadian parts content is 70%. Motorcycles and some heavier trucks may not carry this label; for those, use the VIN method.

A third confirmation: Form 1098-VLI box 7

Starting with interest received in 2026, lenders file Form 1098-VLI for qualifying loans with $600 or more of interest. Box 7 is checked if final assembly occurred in the United States, and boxes 2a–2d repeat the year, make, model, and VIN. The checkbox is helpful, but the regulations make eligibility the borrower's responsibility. If box 7 is blank and your VIN decode says "United States," keep your decode; if box 7 is checked and the decode says otherwise, re-check the VIN before claiming anything.

When to check: before you sign

The assembly test cannot be fixed after purchase, so verify it while you still have choices:

• On the lot: photograph the window sticker and decode the VIN on your phone before negotiating.
• Dealer trades and transfers: the incoming vehicle may come from a different plant than the one you test-drove. Decode the VIN on the buyer's order.
• Factory orders: a VIN is not assigned until the vehicle is scheduled for production. Ask the dealer for it once assigned and decode it before delivery.
• Online purchases: ask for the VIN and a photo of the window sticker before you sign the financing.

What if the sources disagree or are missing?

• Sticker missing: use the VIN; the regulation lets you rely on either.
• Decoder shows blank plant fields: some manufacturer submissions are incomplete. Use the window sticker, or ask the dealer for the factory invoice or Monroney label reprint showing the final assembly point.
• Decoder and sticker disagree: this is rare and usually a typo in the VIN entry. Decode again carefully. If it persists, document both and consider professional advice before claiming.

What assembly does not settle

A "Yes" here clears only one hurdle. You still need a new vehicle, a loan signed after December 31, 2024, a first lien, expected personal use above 50%, and a GVWR under 14,000 lb. A US-assembled lease buyout, used car, or business truck still fails. The car loan interest deduction guide covers each of those tests, and the Working Families Tax Cuts explainer shows how this deduction fits with the other new ones on Schedule 1-A.

Recordkeeping checklist

Keep these for at least three years after you file the last return that claims the deduction:

• the window sticker or a photo of the parts-content box;
• a saved NHTSA decode showing the full VIN and Plant Country;
• the retail installment contract showing the purchase date and lien;
• each year's lender interest statement or Form 1098-VLI.

On your return, you report the VIN on Schedule 1-A, line 22. A wrong or missing VIN makes the interest nondeductible, so copy it from the title or contract rather than retyping from memory.