What does this cost in your state?
California is the costliest state and Arkansas the cheapest; each square shows that state's midpoint of the estimate.
Lower-cost states ($63)MiddleHigher-cost states ($81)
What it shows: CA is the highest at $81 and AR the lowest at $63, across 51 states.
Is this repair covered by an emissions warranty?
Federal rules require carmakers to cover the catalytic converter, the emissions computer and the onboard diagnostic system for 8 years or 80,000 miles, and any part whose failure fails an emissions test for 2 years or 24,000 miles; California requires 3 years or 50,000 miles on every emission part.
| Warranty | Covers | Length |
|---|---|---|
| California, all emission parts | All emissions-related parts | 3 years or 50,000 miles |
| California, high-cost parts | Specific high-cost emission parts listed in the owner manual | 7 years or 70,000 miles |
| Federal, basic | Any part that causes an emissions failure | 2 years or 24,000 miles |
| Federal, extended | Catalytic converters, electronic emissions control unit (ECU), onboard emissions diagnostic device or computer (OBD) | 8 years or 80,000 miles |
What do emissions repairs cost?
Among 46,033 California vehicles repaired to pass a Smog Check in 2025, 39.1% cost over $650 to fix and the average bill was $757.
What it shows: Over $650 is the largest at 39.1%, followed by $1 to $100 at 13.1%; the smallest shown is $501 to $650 at 8.4%.
If my car fails smog, how much of this repair must I pay, and does California help?
California caps required Smog Check repair spending at $650 through a repair cost waiver and its Consumer Assistance Program pays up to $1,450 of repairs for qualifying owners of 1996 and newer cars, so on a typical $73 smog check the program would pay $58 and the owner $15.
| Rule | Amount | What it means at $73 |
|---|---|---|
| CAP repair assistance, model year 1976 to 1995 | up to $1,100 | you pay 20% up to $1,375 of repairs, then everything above $1,100 |
| CAP repair assistance, model year 1996 or newer | up to $1,450 | On a smog check at $73 the program pays $58 and you pay $15 |
| CAP vehicle retirement | up to $2,000 | paid instead of repair when you retire the car |
| Repair cost waiver line (every Smog Check failure) | $650 | A smog check at $73 is under the line, so no waiver |
| Roadside re-failure within a year, model years 2000 to 2006 | 17% after passing, 35% after failing first | 7,886 cars checked in CY 2017-2018 |
After a failed emissions test, who can repair it, and what do repairs cost?
Maryland lists 135 certified emissions repair facilities and New Jersey 332, while Texas inspectors logged about 21,000 emissions repairs costing $3.7 million across its two inspection areas in 2024 and 2025, with a median repair cost of $25 to $299 by category after dropping zero and over-$2,000 entries.
| Program | What the public record shows | Count or figure |
|---|---|---|
| Maryland certified emissions repair facilities | 13 counties; most in Baltimore 31, Montgomery 24, Anne Arundel 17 | 135 facilities |
| New Jersey emission repair facilities | 218 also run private inspections | 332 facilities |
| Texas program evaluation, repair records | repairs logged by inspectors, Dallas-Fort Worth and Houston areas, 2024 and 2025 | about 21,000 repairs, $3.7 million |
| Texas repair cost per repair (median and mean ranges) | by repair category, after dropping zero entries and costs above $2,000 | median $25 to $299, mean $82 to $415 |
| Texas repair records logged at zero cost | inspectors enter the cost by hand; the report warns of entry errors | 68.1% of records |
Does my county fall under federal smog rules or breathe unhealthy air?
Among 203 counties EPA currently lists as nonattainment for ozone or fine particles, the largest are Los Angeles County, CA (10,013,976 residents), Cook County, IL and Harris County, TX.
What it shows: Los Angeles County, CA is the largest at 10,013,976, followed by Cook County, IL at 5,275,555; the smallest shown is Queens County, NY at 2,405,425.
Which emission standard was my car certified to?
EPA's certification records show 100.0% of model year 2014 light-duty carlines certified to the older Tier 2 exhaust standard and 79.1% of model year 2026 carlines certified to Tier 3 Bin 50 or cleaner, so the catalytic converter and sensors a car needs depend on its model year (one count per carline, not per car sold).
| Model year | Tier 2 (older standard) | Tier 3 Bin 70 to 160 | Tier 3 Bin 20 to 50 (cleaner) | Tier 3 Bin 0 (zero emission) |
|---|---|---|---|---|
| 2014 | 100.0% | 0.0% | 0.0% | 0.0% |
| 2016 | 95.6% | 3.1% | 1.2% | 0.1% |
| 2018 | 3.1% | 82.4% | 12.8% | 1.8% |
| 2020 | 2.4% | 69.8% | 24.7% | 3.1% |
| 2022 | 0.2% | 53.2% | 38.3% | 8.3% |
| 2024 | 0.3% | 34.5% | 43.5% | 21.7% |
| 2026 | 0.1% | 20.7% | 48.1% | 31.0% |
How often does this part fail a real inspection, by car age?
In 2,102,125 New Jersey initial inspections in 2025, 14.3% of cars aged 16+ years failed the emissions test against 2.8% of cars under 3 years, about 5 times as often (record counts, not a sample).
What it shows: 16+ is the largest at 14.3%, followed by <3 at 2.8%; the smallest shown is 3-4 at 2.6%.
A smog check cost of $48–$98 is the calculator's default for a regular car in a state with a regulated program. Your vehicle type and your state move that number most. A diesel costs more, and a state without strict rules often costs far less.
What does a smog check cost cover, and what does it leave out?
The price pays for a technician to test your car's emissions and report the result. It doesn't pay for any fix. If the car fails, you'll get a report and a list of what to repair before a retest.
Check what the quote includes before you book. Some shops quote the test alone, and others add state certificate or transmission fees at the counter. Ask for the total you'll walk out paying.
The estimate also leaves out repairs, a retest fee if the shop charges one, and your local taxes. It's the cost of the test, not of passing it.
How much does a smog check cost by vehicle type and state?
The calculator prices the test by vehicle type and by state group. Find the row that matches your car.
| Situation | Estimate |
|---|---|
| Regular car, regulated state (default) | $48–$98 |
| Diesel, regulated state | $72–$152 |
| Any car, other state | $20–$50 |
| Classic or pre-1976 vehicle | $0 (exempt in most states) |
Diesels cost more because the test takes more work. Higher-cost states like New York and New Jersey sit near the top of the range, while rural areas sit near the bottom.
Use the calculator above with your own state to see where your price lands.
How do you know you need a smog check, and how urgent is it?
Most people need one because registration is due, the car is being sold, or it just moved into a state that requires one. The deadline comes from your registration notice, so book early.
A warning light changes the plan. Owners told NHTSA that a warning light came up in 44% of 41 complaints that name a smog check or a failed emissions test. A car with the check engine light on usually won't pass, so paying for the test first wastes money.
If the light is on, get the code read before you test. A free or cheap code read tells you whether you're heading for a repair, and you can fix it before the test fee is spent.
How do you get a fair quote for a smog check?
Call two or three stations and ask three things. What is the full price with every fee included? Is the retest free, and for how long? Is the station test-only or does it also repair cars?
A test-only station has no reason to find a problem so it can sell you the fix. If your car fails, take the written report to a second shop for a repair quote.
Compare each price with the calculator range for your state. A quote well above the top of the range is worth a second call.
What does the estimate leave out?
The calculator doesn't know your county's rules, your car's model year exemption or any coupon a station is running. Some areas test every year and others every two years. Some test only certain counties.
The big unknown is whether the car passes. Of the 41 complaints in our data, 59% also name the emissions test. When a car fails, the repair can cost many times what the test did. Treat the test price as the small part of the bill.
Frequently asked questions
Do I pay for a smog check if my car fails?
Yes, usually you pay the test fee either way. The pass certificate fee may only apply on a pass in some states. Ask the station how it handles a fail before the test starts.
Is a diesel smog check priced differently?
Yes. The calculator shows a diesel at $72–$152 in a regulated state against the regular-car default. Shops charge more because the test is longer.
Sources
Data shown on this page
- CalcScrape calculator model scaled by BEA Regional Price Parities data from 2024
- U.S. Code of Federal Regulations, 40 CFR 85.2103, and the California Air Resources Board warranty fact sheet file downloaded 2026-10-05
- California Bureau of Automotive Repair, Smog Check Executive Summary Report 2025 data from 2025
- California Bureau of Automotive Repair: Smog Check Reference Guide, Consumer Assistance Program repair assistance page, and 2019 Smog Check Performance Report data from 2025
- Maryland Department of the Environment (opendata.maryland.gov 7gas-4kz4), State of New Jersey open data (9qpt-bnm4), Texas Commission on Environmental Quality, Evaluation of the Texas Vehicle Emissions Inspection and Maintenance Program (2026) data from 2026
- EPA Green Book, Currently and previously designated nonattainment areas by county; county population from the 2020 Census file downloaded 2026-09 (EPA export 2026-09-30)
- U.S. EPA, Annual Certification Data for Vehicles, light-duty vehicle models 2014-present (exhaust standard of every certified carline) file downloaded 2026-10
- New Jersey Motor Vehicle Commission, Vehicle Inspection Data file downloaded 2026-10
Terms: US government data, public domain.
Modeled: our estimate, not a quote. Rule: a published legal rule, not a measurement; whether it covers a given repair depends on the car and the facts. Observed: records as filed; owner reports are unverified and are not failure rates.
What is our own estimate
The price range comes from our calculator's formula. Its parts prices, labor hours per job and shop-rate tiers are CalcScrape estimates, not a published price dataset. Checked against RepairPal's range ($61–$90) on 2026-10-05: our default's midpoint is 3% below the middle of that range. Methodology