Colorado DOT Number Requirements: Two Agencies, Two Different Door Markings

Colorado DOT number requirements come from two different agencies, and they ask for two different things on the door. The Colorado State Patrol rules say an intrastate carrier marks its vehicles with the Colorado assigned USDOT number, preceded by "USDOT" and followed by "CO" (Colorado State Patrol rules). The Public Utilities Commission has its own marking rule for the for-hire carriers it regulates. Find out which agency covers your truck first, then read the matching section below.

Two agencies, two rules

• Colorado State Patrol (CSP), Motor Carrier Safety Section. Its rules cover commercial vehicles in Colorado, in both interstate and intrastate transportation. This is where the USDOT number plus CO comes from.
• Colorado Public Utilities Commission (PUC). Its transportation rules cover carriers that hold a PUC certificate or permit. The rules name common carriers such as taxicab, shuttle and sightseeing service, contract carriers, limited regulation carriers such as charter buses and limousines, towing carriers and movers (PUC rules, 4 CCR 723-6).

A truck can be in one group, both or neither, so do not assume a rule applies because a friend in another trade follows it.

The State Patrol rule: USDOT, number, CO

CSP's rules adopt the federal safety regulations for intrastate carriers too, and then change a few of them. One change says each motor carrier that operates in intrastate commerce must apply for and receive a Colorado assigned USDOT number before it starts operating in the state, and must update that information every 24 months. Another change, to the federal marking section, reads in part: intrastate carriers must mark their vehicles with the Colorado assigned USDOT number, preceded by the letters "USDOT" and followed by the suffix "CO," with the example USDOT 1234567 CO (CSP rules).

Two details in that same text are worth knowing:

• The rule says identification numbers for intrastate motor carriers are issued through the Colorado State Patrol, Motor Carrier Safety Section, and that only the legal name or a single trade name may be used on the application.
• For intrastate carriers with a GVWR or GCWR from 10,001 to 26,000 pounds that are not carrying 16 or more passengers or placarded hazardous materials, the rule lets the marking go on the trailer or secondary unit when the self-propelled unit's GVWR is 10,000 pounds or less. Repossessors operating intrastate are not subject to the federal marking section under this rule.

The copy of the rules we read refers to the federal regulations as they stood on October 1, 2013, so ask CSP whether a newer version is in force. We did not read the state statute that defines a "commercial vehicle," so we state no weight line for it. CSP is the place to ask.

The PUC rule: CO PUC plus your designation

The PUC's exterior marking rule is Rule 6015. For a motor vehicle it covers, the markings must appear on both sides or on the front and back of the vehicle, contrast sharply with the background, and be readily legible in daylight from 50 feet "but in no case be less than three inches tall." It asks for the name or trade name as set out in the carrier's certificate or permit, and the letter and number designation of that certificate or permit, preceded by "CO PUC" or "PUC." The marking can be permanently affixed or a removable device (PUC rules, 4 CCR 723-6).

Rule 6015 sets those words and that three-inch minimum for PUC markings only. It is not a federal rule and it is not the CSP rule. Luxury limousines have their own rule, 6303, with a different format.

The federal baseline both rules sit on

Federal marking rules ask for the carrier's legal name or a single trade name, the USDOT number, markings on both sides, colors that contrast sharply with the background, and legibility from 50 feet in daylight with the vehicle stopped (49 CFR 390.21T). That section sets no letter height. Our display rules page has it in plain words, and how big USDOT numbers need to be covers size.

A worked example

Pikes Peak Hauling is a made-up Colorado company with a dump truck that stays in the state. With the made-up CSP number 2345678, its door reads:

• PIKES PEAK HAULING
• USDOT 2345678 CO

Now take a made-up towing company, Summit Tow, with a PUC permit. Under Rule 6015 its door would carry the name as it appears on the permit, then "CO PUC" followed by the letter and number designation exactly as printed on that permit, in letters at least three inches tall. We do not invent a designation, because the format is whatever your permit says.

Slips to avoid

• Putting CO in front of the number. The CSP text puts it after.
• Printing the PUC prefix on a truck that is not PUC-regulated, or leaving it off one that is.
• A trade name that is not the one on the application or permit.
• A number on the door before it has been assigned to you.

Our examples and mistakes guide has more.

Where each number comes from

The CSP rule says intrastate numbers are issued through the Colorado State Patrol, Motor Carrier Safety Section. If you run interstate, the USDOT number comes from FMCSA, and new applications go through Motus at motus.dot.gov. A PUC certificate or permit number comes from the PUC. We do not issue numbers and cannot look them up. Not sure whether you need a federal number at all? Try our free USDOT number checker.

Questions to ask before you order

Write down the date and who answered.

1. To CSP: must my truck carry a Colorado assigned USDOT number, and does the 10,001 to 26,000 pound carve-out apply?
2. To the PUC: do I hold, or need, a certificate or permit, and what exact wording goes on the vehicle?
3. To either agency: which version of the rule is in force today?

Ordering the decal

The USDOT Decal with CO Suffix prints USDOT, your number and CO on one rectangle, from $18.99 per decal at 12 inches. You choose width (12, 18 or 24 inches, which are decal widths and not legal sizes), lettering color and background color, and you can add your company name above the number. For a PUC marking, the Make-Your-Own 5-Line Lettering takes the lines you type. We print what you enter, so confirm the wording first. For other states see USDOT number requirements by state.