Fines for no DOT number on your truck: what gets cited and the max
What gets cited
The marking rule is 49 CFR 390.21T (the eCFR shows 390.21 as suspended and 390.21T in force; most people still say 390.21). Common problems that fall under it:
- no name or USDOT number on the truck at all;
- marking on one side only (it must appear on both sides);
- "DOT 1234567" without the letters USDOT;
- a name that doesn't match the legal or single trade name on your MCS-150;
- letters that don't contrast sharply or can't be read from 50 feet in daylight;
- faded or peeling lettering (it must be maintained so it stays legible);
- another carrier's name with no "operated by" in front of yours.
Federal maximum penalties (as of October 2026)
49 CFR part 386 Appendix B, as shown in the eCFR in October 2026 (last amended July 21, 2026), lists these maximums for violating parts 390 through 399 outside of recordkeeping:
- A person or entity (the carrier): not to exceed $19,246 for each violation, under Appendix B (a)(3).
- A driver: not to exceed $4,812, under Appendix B (a)(4).
These amounts are adjusted for inflation over time, so check the current Appendix B. They are maximums. We could not find a published fixed fine for a marking violation, and state and local penalties for roadside citations vary by state.
Does it hurt your CSA scores?
FMCSA's Safety Measurement System scores carriers in BASICs using roadside violations listed in SMS Methodology Appendix A, each with a severity weight. In Appendix A version 3.21 (revised May 2026), we did not find any 390.21 or 390.21T marking violation in any BASIC. So, per that list, a marking write-up doesn't carry a CSA severity weight. It can still show up on the inspection report and in an audit, so fix it anyway.
How to avoid it
- Check your Legal Name and DBA Name on SAFER (DOT number lookup).
- Letter both sides with that name and "USDOT" plus your number.
- Size it to read from 50 feet; see USDOT number size requirements.
- Replace lettering once it fades or peels.
Our USDOT truck lettering is premium cast vinyl rated 5+ years outdoors, both doors from $59 with free shipping.
Related questions
Is a missing DOT number an out-of-service violation?
We couldn't verify that from a public official source, so we won't say. Ask your state's commercial vehicle enforcement agency.
Is the fine per truck?
Appendix B states the carrier maximum per violation. How violations are counted in a given case is up to the enforcement action, so confirm with FMCSA or your attorney.
Do states fine for this too?
States can adopt the federal marking rule; Washington, for example, adopts 49 CFR 390.21T in WAC 446-65-010. State penalties vary, so check with your state's enforcement agency.
Does a marking violation affect my CSA score?
Per FMCSA's SMS Methodology Appendix A version 3.21 (May 2026), 390.21 marking violations are not listed in any BASIC, so they don't carry a severity weight.
- 49 CFR part 386 Appendix B, Penalty schedule (eCFR, as of October 2026)
- FMCSA SMS Methodology Appendix A, violations list, version 3.21 (May 2026)
- FMCSA SMS Methodology, version 3.21 (methodology revised May 2026)
- Washington State Patrol, How to Mark Your Vehicle (cites WAC 446-65-010 adopting 49 CFR 390.21T)
- 49 CFR 390.21T, Marking of self-propelled CMVs (the version in effect)
- 49 CFR 390.21, Marking of self-propelled CMVs (suspended, see effective date note)
- 49 CFR 390.21T, Marking of self-propelled CMVs (the version in effect; 390.21 is suspended)
- FMCSA, Do I need a USDOT number?
Checked against the current regulations September 2026. This is a plain-English summary, not legal advice. When your situation is unusual, ask the CHP, FMCSA or CSLB directly.