A STAR station is a Montana-certified repair shop that can test your vehicle's emissions and fix problems on the spot

Montana's STAR (Sensible Transportation and Repair) program lets you get your smog check and any needed repairs at the same location. A STAR station is a regular auto repair shop that has passed state inspection and holds a current STAR certificate. The main difference from a regular test-only station is that STAR shops can both diagnose why your vehicle failed and perform the repairs without sending you elsewhere.

You do not have to use a STAR station — you can get tested at any certified Montana emissions test station. But if your vehicle fails, a STAR station saves you a trip. You walk in, get tested, learn what needs fixing, and often leave with the work done the same day.

Key Takeaways

  • STAR stations are repair shops certified by Montana to perform both emissions testing and repairs in one location.
  • You can find STAR stations through the Montana Department of Environmental Quality website or by calling your local air quality office.
  • STAR stations charge a testing fee (the amount varies by shop) plus the cost of any repairs your vehicle needs.
  • If your vehicle passes the test at a STAR station, you receive your certificate when ready and do not need to visit another location.

How STAR stations differ from test-only stations

A test-only station runs your vehicle through the emissions test, gives you the result, and that is where their job ends. If you fail, you must take your car to a repair shop, get it fixed, then return to a test station for a retest. This can mean two or three separate trips across town.

A STAR station combines both steps. The technician tests your vehicle, identifies the emissions problem, repairs it, and retests you — often within a few hours. You pay one testing fee plus repair costs, rather than paying two testing fees at two different shops. STAR stations must meet the same technical standards as test-only stations and are inspected regularly by the state.

Finding a STAR station near you

The Montana Department of Environmental Quality maintains a searchable list of all certified STAR stations on its website. You can search by county or city to find shops in your area. The list includes the shop's name, address, phone number, and hours.

You can also call your local air quality office or county health department — they keep current lists and can tell you which STAR stations are accepting customers. Some shops may have a waiting list during peak testing season (usually fall and winter), so calling ahead to ask about wait times is worth doing.

What to bring and what to expect

Bring your vehicle registration and proof of insurance. The technician will run your vehicle through the standard Montana emissions test, which takes 10 to 20 minutes. If you pass, you receive your certificate on the spot and are done.

If you fail, the technician will explain what failed and what repairs are needed. At a STAR station, you can authorize repairs right there. Common repairs include replacing an oxygen sensor, fixing a vacuum leak, or replacing a catalytic converter. Repair time depends on the problem — straightforward fixes may take an hour, while others take longer. Once repairs are complete, the station retests your vehicle at no additional testing fee.

Testing fees and repair costs

Montana sets a maximum testing fee that STAR stations can charge, but the exact amount varies by shop and may change year to year. Call ahead to ask what the current testing fee is. Repair costs depend entirely on what your vehicle needs and vary widely — a sensor replacement costs far less than a catalytic converter.

Some STAR stations offer estimates before starting work, and many will discuss repair options with you if the initial diagnosis suggests expensive work. If you want a second opinion or prefer to use a different shop for repairs, you can take your test results elsewhere — nothing requires you to have repairs done at the testing station.

What happens if repairs do not fix the problem

If your vehicle is retested after repairs and still fails, the STAR station must retest you at no additional charge. You only pay for repairs that were actually performed. If the same problem persists, you may need to consult a different technician or specialist shop, particularly if the vehicle has an unusual or complex emissions issue.

Montana law requires that any shop performing emissions-related repairs must stand behind that work for a set period. If you have questions about warranty or guarantees on repairs, ask the STAR station before authorizing work.

When to choose a STAR station versus a test-only station

Choose a STAR station if you think your vehicle might fail or if you want the convenience of one-stop service. Choose a test-only station if your vehicle is in good condition and you are confident it will pass — test-only stations are sometimes faster if there is no wait, and you avoid paying for repair capability you may not need.

If you have already had repairs done elsewhere and just need a retest to confirm the work, either type of station works. The test itself is identical regardless of where you go.

Frequently Asked Questions

Can I get my emissions test at a STAR station if I do not want repairs done there?

Yes. STAR stations perform the same test as any other certified station. If you fail and prefer to have repairs done elsewhere, you can take your test results to another shop. You only pay the testing fee at the STAR station.

How long does the whole process take at a STAR station?

Testing alone takes 10 to 20 minutes. If you pass, you are done. If you fail and authorize repairs, the total time depends on what needs fixing — anywhere from one to four hours for most common repairs. Call ahead to ask about current wait times.

Do I need an appointment at a STAR station?

Policies vary by shop. Some accept walk-ins, while others prefer appointments, especially during busy seasons. Call the station before you go to ask about their process and current availability.

What if my vehicle has a check engine light but I am not sure what is wrong?

A STAR station can run the emissions test and diagnostic scan to identify the problem. You will learn what is causing the light and what repairs are needed. You can then decide whether to have the work done there or take the information elsewhere.

Is there a warranty on repairs done at a STAR station?

Montana law requires emissions-related repairs to carry a warranty, but the length and terms vary by shop. Ask the STAR station about their specific warranty before authorizing any work.