Disclosure: this guide contains referral links, marked where they appear. Market data is independently measured from public sources on the dates shown.
Colorado has the best kei vehicle law in the United States. Not the most permissive — that is a different contest — but the most carefully drafted, by a wide margin. HB25-1281 closes, in a single bill, nearly every failure mode I have documented in other states.
It also has the longest wait in the country. The governor signed it on May 9, 2025. It takes effect July 1, 2027, and it applies to applications submitted on or after January 1, 2028. So the answer for a Colorado buyer today is: yes, eventually, and the law is on your side — but you cannot register one for another two years.
I research Japan’s used vehicle market from Sapporo. Of the state statutes I have read for this site, this is the one to copy.
The Short Answer
- Road registration: yes — from January 1, 2028. Not before. The act takes effect July 1, 2027 and applies to applications from January 1, 2028.
- Roads: anything posted at 55 mph or less, plus you may cross a faster road at an at-grade intersection. No limited-access highways.
- Kei vehicles become “motor vehicles” under Colorado law rather than a special sub-class — including for insurance purposes.
- The length limit is 140 inches, which actually fits the trucks Americans import. Most states that wrote a limit chose 130.
- The speed requirement is a minimum, not a maximum: a kei vehicle must be capable of at least 50 mph.
- The state is barred from declaring these trucks unroadworthy based on design, and from requiring an inspection just because a vehicle is a kei vehicle.
- Emissions are tested with a two-speed idle test, not a dynamometer, against the standards for the model year it was built.
The Definition Colorado Wrote
The bill adds a new definition at C.R.S. 42-1-102(45.3). From the enrolled bill text:
“KEI VEHICLE” MEANS A VEHICLE THAT: (a) IS POWERED BY AN INTERNAL COMBUSTION ENGINE WITH A DISPLACEMENT OF ONE THOUSAND CUBIC CENTIMETERS OR LESS OR AN ELECTRICAL MOTOR OF FIFTY-SIX THOUSAND WATTS OR LESS; (b) IS SIXTY-SEVEN INCHES OR LESS IN WIDTH; (c) IS ONE HUNDRED FORTY INCHES OR LESS IN LENGTH; (d) TRAVELS ON FOUR OR MORE TIRES IN CONTACT WITH THE GROUND; (e) HAS A TOP SPEED OF AT LEAST FIFTY MILES PER HOUR; (f) HAS AN ENCLOSED PASSENGER CAB; (g) WAS IMPORTED INTO THE UNITED STATES; AND (h) (I) WAS TWENTY-FIVE YEARS OLD OR OLDER WHEN IMPORTED INTO THE UNITED STATES; OR (II) IS TWENTY-FIVE YEARS OLD OR OLDER AND WAS PREVIOUSLY ISSUED A TITLE IN THE UNITED STATES.
Two clauses in there are the reason this statute is better than everyone else’s.
140 inches. Pennsylvania, North Carolina and Massachusetts’ pending bill all write 130 inches, which is 3,302 mm — the Japanese kei length limit as it stood until October 1998. Every kei truck built from 1999 measures 3,395 mm, or 133.7 inches, and is therefore outside those definitions on paper. Colorado wrote 140 and left more than six inches of headroom. Somebody checked the vehicle before writing the number. The comparison of state definitions lays out how differently states handled this.
“A TOP SPEED OF AT LEAST FIFTY MILES PER HOUR.” Read that again — it is a floor, not a ceiling. Every other state I have read either caps speed or ignores it. Colorado requires the vehicle to be capable of 50 mph, which excludes golf carts and side-by-sides by capability rather than by measuring them, and simultaneously acknowledges that a kei truck belongs in traffic rather than beside it. It is the same drafting instinct as Indiana’s minimum engine displacement, applied to the thing that actually matters on a road.
Note also clause (g): “WAS IMPORTED INTO THE UNITED STATES.” Like Nebraska, Colorado named what it was regulating instead of writing a general rule and hoping.
What the Bill Pre-empts
This is the part that makes HB25-1281 remarkable, and it gets almost no attention in buying coverage. Colorado did not just permit these vehicles — it went through the ways other states say no and shut each one off.
The “not roadworthy” refusal. New C.R.S. 42-6-102(15)(c)(I):
“IN ACCORD WITH ITS DESIGN AND USE” PRECLUDES A KEI VEHICLE FROM BEING DECLARED TO BE NOT ROADWORTHY BASED ON ITS DESIGN OR MANUFACTURING PARAMETERS.
That sentence exists because it is the standard objection. It is what Georgia’s revenue bulletin relies on and what PennDOT says publicly. Colorado wrote it out of the law.
The extra inspection. New C.R.S. 42-5-202(5) bars the Department of Revenue, its agents, the Colorado State Patrol, its agents, or anyone contracted to them from requiring an inspection “BECAUSE IT IS A KEI VEHICLE… OR HAS THE DESIGN OR MANUFACTURING PARAMETERS OF A KEI VEHICLE.” Compare Ohio, where a police inspection is a mandatory condition of the local ordinance that lets you drive at all.
The impossible emissions test. Colorado’s emissions programme normally uses a loaded-mode transient dynamometer cycle. The bill carves kei vehicles out of that and specifies a two-speed idle test instead, and sets the standard: “TO BE ISSUED A CERTIFICATE OF EMISSIONS COMPLIANCE, A KEI VEHICLE MUST PASS THE EMISSIONS STANDARDS FOR THE MODEL YEAR IT WAS MANUFACTURED.”
That is the answer to a question I could not answer for Arizona, where a 1990s Japanese-market truck with no US diagnostic port falls into an emissions programme with no published guidance on how to test it. Colorado wrote the method and the benchmark into statute.
The dealer problem. New C.R.S. 44-20-432.5 provides that a licensed dealer “IS NOT LIABLE FOR ANY DAMAGES THAT ARE DIRECTLY OR INDIRECTLY ATTRIBUTABLE TO SELLING A KEI OFF-ROAD VEHICLE THAT IS NOT MANUFACTURED IN ACCORDANCE WITH UNITED STATES FEDERAL SAFETY STANDARDS.” Liability exposure is a large part of why franchised dealers will not touch these vehicles. Colorado addressed it directly.
Insurance. Section 1 of the bill amends C.R.S. 10-4-601(6) so that “motor vehicle” in the auto insurance part includes a kei vehicle. In most states an owner has to persuade an insurer that an unfamiliar import is insurable; in Colorado the definition does that work.
Where You Will Be Able to Drive It
New C.R.S. 42-4-109.7 is the operating rule:
A PERSON SHALL NOT DRIVE A KEI VEHICLE ON A ROADWAY THAT HAS A SPEED LIMIT GREATER THAN FIFTY-FIVE MILES PER HOUR; EXCEPT THAT A PERSON MAY DRIVE ACROSS A ROADWAY WITH A SPEED LIMIT GREATER THAN FIFTY-FIVE MILES PER HOUR AT AN AT-GRADE INTERSECTION. A PERSON SHALL NOT DRIVE A KEI VEHICLE ON A LIMITED-ACCESS HIGHWAY.
A violation is a Class B traffic infraction — an ordinary ticket, not a titling problem.
The at-grade crossing exception matters more than it looks. A 55 mph rule without it strands you whenever your route crosses a 65 mph highway, which in rural Colorado is constantly. North Carolina has the same crossing allowance; Florida’s 35 mph rule is far more confining.
The Wait, and What to Do With It
The timeline is the one genuinely bad thing about Colorado’s position, and it is worth being precise rather than vague about it:
- May 9, 2025 — signed. The bill passed the House 64–1 and the Senate 35–0.
- July 1, 2027 — the act takes effect.
- January 1, 2028 — it applies to applications submitted on or after this date. This is when you can actually register.
Nearly three years between signature and a plate. The delay is administrative — the Department of Revenue and the emissions programme need to build the processes the bill requires — but it is still nearly three years.
What that means practically:
- Private-property use is legal now, as it is everywhere. Ranch, acreage, mountain property, ski-area maintenance, orchard work. No plate needed and nothing about the timeline affects it.
- Buying now is defensible if you have land to use it on. You are not waiting for permission to own the truck, only to plate it.
- Buying now purely to drive in 2028 is a judgement call. You would be paying two years of storage and depreciation for a plate you cannot use, and Japanese prices have not been rising fast enough to make that a good trade.
- The eligible pool improves while you wait. By January 2028 the 25-year line reaches 2003 builds, and there is more supply behind it than in front — the 25-year rule guide has the pipeline.
If you want a plate sooner and can choose where you live, the open states are worth reading: Michigan registers them like ordinary vehicles, Arizona has no kei-specific restriction, and Texas created a class in 2025. The 50-state guide has all of it.
Why This Statute Matters Outside Colorado
If you are an owner or an advocate in a state that has said no, HB25-1281 is the single most useful document you can put in front of a legislator, for three reasons.
First, it passed 64–1 and 35–0. This is not a partisan fight anywhere it has been put to a vote.
Second, it answers the objections instead of ignoring them. A legislator worried about safety can be shown a bill that keeps these vehicles off limited-access highways, requires a 50 mph minimum capability, and keeps the emissions requirement in place while specifying a test the vehicle can actually take. It is not a carve-out; it is a regulatory framework.
Third, it fixes the drafting error that is quietly spreading. Massachusetts’ H.4053 sits in House Ways and Means with a 130-inch length limit in it. Colorado shows what number to write instead. That is a one-line amendment with a working precedent behind it.
For Reference: What These Trucks Cost
Whether you are buying now for property use or planning for 2028, this is the Japan-side market, measured August 19, 2026 — every eligible truck listed publicly in Japan, at ¥159/USD:
| Model | Listings in Japan | Median price in Japan |
|---|---|---|
| Subaru Sambar | 78 | ¥364,000 (≈$2,289) |
| Mitsubishi Minicab | 64 | ¥394,000 (≈$2,478) |
| Honda Acty | 80 | ¥398,000 (≈$2,503) |
| Suzuki Carry | 99 | ¥399,000 (≈$2,509) |
| Daihatsu Hijet | 60 | ¥453,000 (≈$2,849) |
Landed cost runs about $4,800–6,700 depending on specification, itemised in the cost guide, with the raw dataset published so you can recount any figure.
Three Colorado-specific notes on specification. Buy 4WD — it is ordinary equipment on this supply rather than a rare option, and at altitude on snow and gravel it is the whole point; the off-road guide has the measured shares by model. Be realistic about altitude. A naturally aspirated 660cc engine loses power with air density, and Colorado passes are where that becomes obvious — the specs guide has the honest flat-ground figures, and you should mentally subtract from them. A turbocharged or supercharged variant is worth seeking here more than almost anywhere else. And Colorado salts and sands its highways, so the underbody advice from the Michigan guide applies: read the auction sheet for corrosion codes rather than paint grade.
If you have land to use it on, there is no reason to wait — and if you are buying for 2028, the specification advice above is what to hold out for. CAR FROM JAPAN lists eligible trucks with the inspector’s auction sheet attached, and my referral code takes $100 off a first purchase: enter KEITRUCK at the order step (referral link). Look for 4WD with boost, and check the corrosion codes before the paint grade.
FAQ
Are kei trucks legal in Colorado?
They will be registrable for road use from January 1, 2028. HB25-1281 was signed on May 9, 2025, takes effect July 1, 2027, and applies to applications submitted on or after January 1, 2028. Private-property use is legal now and always was.
Why is there such a long delay?
The act’s own effective-date section sets July 1, 2027, with applications from January 1, 2028 — the interval is for the Department of Revenue and the emissions programme to build the processes the bill requires. Nothing in the delay reflects doubt about the policy: the bill passed the House 64–1 and the Senate 35–0.
Where will I be able to drive it?
Any roadway posted at 55 mph or less, and you may cross a faster roadway at an at-grade intersection. Limited-access highways are prohibited. A violation is a Class B traffic infraction.
Will my truck fit Colorado’s definition?
Almost certainly. The limits are 1,000cc, 67 inches of width and 140 inches of length, against a kei truck’s 660cc, about 58 inches and 133.7 inches. The one requirement to check is the minimum: the vehicle must be capable of at least 50 mph, which a healthy kei truck is but a tired one on tall tyres may not be.
Will it need an emissions test?
Yes, but a test it can take. The bill exempts kei vehicles from the loaded-mode dynamometer cycle and specifies a two-speed idle test instead, judged against the emissions standards for the model year the vehicle was built.
Can Colorado refuse my truck as unsafe?
Not on the basis of what it is. The bill provides that “in accord with its design and use” precludes a kei vehicle from being declared not roadworthy based on its design or manufacturing parameters, and separately bars the Department of Revenue and the State Patrol from requiring an inspection because a vehicle is a kei vehicle. An individual truck can still fail for being genuinely broken.
Should I buy now or wait until 2028?
Buy now if you have property to use it on, because none of the timeline affects private-property use. If your only purpose is road driving, waiting costs you nothing and the eligible supply grows in the meantime.