Fail the CDL knowledge test once and the first question is simple: how soon can you try again? The honest answer is that it depends entirely on which state you’re testing in — the FMCSA sets the federal knowledge content every state must test, but retake policy (wait time, attempt limits, retest fees) is left to each state’s own licensing agency. We researched every state’s own official page directly rather than publish one generic national rule.
| State | Retake policy (as published by the state) |
|---|---|
| Alabama | Not specified on the state’s official page (unconfirmed) |
| Alaska | Not specified on the state’s official page (unconfirmed) |
| Arizona | Must wait until the next business day to retake a failed knowledge test |
| Arkansas | Not specified on the state’s official page (unconfirmed) |
| California | Official DMV CDL page states applicants get three attempts at each knowledge test and three attempts at the skills test, but does not state a mandatory wait time between attempts. Secondary sources cite a 3-day wait for CDL retests -- UNCONFIRMED on an official page in this pass. |
| Colorado | Not specified on the state’s official page (unconfirmed) |
| Connecticut | No fixed waiting period specified on the official page; a failed knowledge test requires scheduling a new appointment, submitting a fresh application (Form R-229a), and paying the test fee again |
| Delaware | Not specified on the state’s official page (unconfirmed) |
| Florida | Not specified on the state’s official page (unconfirmed) |
| Georgia | Not specified on the state’s official page (unconfirmed) |
| Hawaii | Not specified on the state’s official page (unconfirmed) |
| Idaho | 3 days, plus a $5.00 retest fee (per ITD's Ten Steps to Getting an Idaho CDL guide) |
| Illinois | Not specified on the state’s official page (unconfirmed) |
| Indiana | Not specified on the state’s official page (unconfirmed) |
| Iowa | Not specified on the state’s official page (unconfirmed) |
| Kansas | Knowledge test reexam within 6 months: $1.50; reexam after 6 months from last exam: treated as new $3.00 abandonment-adjacent first-attempt fee (per Kansas Credential Fee Chart notes) |
| Kentucky | Written/knowledge test: must wait 24 hours to retake if failed (confirmed directly on official drive.ky.gov page). Skills test: may be retaken as many times as needed while the CLP remains valid and fees are current; no fixed wait period stated. |
| Louisiana | Not specified on the state’s official page (unconfirmed) |
| Maine | Not specified on the state’s official page (unconfirmed) |
| Maryland | Not specified on the state’s official page (unconfirmed) |
| Massachusetts | Not specified on the state’s official page (unconfirmed) |
| Michigan | Not specified on the state’s official page (unconfirmed) |
| Minnesota | No explicit 'must wait N days' language found on official pages; what is confirmed is the fee escalation structure above (extra $10/$20 charges apply only from the 3rd attempt onward, implying no separate wait/fee penalty for the first two retakes) |
| Mississippi | Reported by secondary test-prep sources as 1 business day after a 1st or 2nd knowledge-test failure, and a 30-day wait after a 3rd failure — NOT confirmed from an official MS DPS page or manual text |
| Missouri | Not specified on the state’s official page (unconfirmed) |
| Montana | If pre-trip inspection or basic-control skills steps are failed, must wait at least 24 hours to retest. If those pass but the on-road driving portion is failed, must wait at least 1 week to retest (confirmed on official MVD page). |
| Nebraska | Not specified on the state’s official page (unconfirmed) |
| Nevada | Not specified on the state’s official page (unconfirmed) |
| New Hampshire | Not specified on the state’s official page (unconfirmed) |
| New Jersey | Knowledge test: 7-day wait after failure. Road/skills test: at least 14 days (2 weeks) wait after failure. NOTE: an internal inconsistency exists across official MVC pages regarding test-score validity — one page states the $125 test receipt is valid for 180 days, another states test scores are valid for 360 days; this discrepancy is unresolved and should be re-verified before publishing. |
| New Mexico | Not specified on the state’s official page (unconfirmed) |
| New York | Not specified on the state’s official page (unconfirmed) |
| North Carolina | Not specified on the state’s official page (unconfirmed) |
| North Dakota | Knowledge test: one attempt allowed per day ($5 per attempt), per official page. An unverified secondary claim suggests a 14-day wait after 3 failed attempts -- not confirmed on a primary source. |
| Ohio | Not specified on the state’s official page (unconfirmed) |
| Oklahoma | First three attempts may be retaken at least 1 day apart (or as instructed by the examiner); fourth attempt onward requires at least a 30-day wait between tests. A $4.00 fee applies to each failed attempt. (Policy appears on Service Oklahoma's general Drive Test Center page, which covers both regular and CDL testing.) |
| Oregon | Not specified on the state’s official page (unconfirmed) |
| Pennsylvania | Not specified on the state’s official page (unconfirmed) |
| Rhode Island | 7 days -- official: 'If you fail an exam, you must wait seven days before retaking that exam' |
| South Carolina | Skills test: 2 business days after 1st failure; 7 calendar days after 2nd failure; 30 calendar days after 3rd or subsequent failure (dmv.sc.gov CDL Testing page) |
| South Dakota | 2-day waiting period between when a skills test is scheduled and when it can be taken, per sdtruckinfo.sd.gov. Knowledge-test-specific retake wait time not found on an official page. |
| Tennessee | Not specified on the state’s official page (unconfirmed) |
| Texas | Not specified on the state’s official page (unconfirmed) |
| Utah | Not specified on the state’s official page (unconfirmed) |
| Vermont | Not specified on the state’s official page (unconfirmed) |
| Virginia | Not specified on the state’s official page (unconfirmed) |
| Washington | Not specified on the state’s official page (unconfirmed) |
| West Virginia | Not specified on the state’s official page (unconfirmed) |
| Wisconsin | Not specified on the state’s official page (unconfirmed) |
| Wyoming | Not specified on the state’s official page (unconfirmed) |
The range is wider than most people expect
On one end, Arizona lets you retake a failed knowledge test the very next business day. On the other, Oklahoma and South Carolina both escalate to a real 30-day mandatory wait once you’ve failed three or more times — a policy clearly designed to stop repeated same-day guessing rather than genuine studying between attempts. Rhode Island’s rule is simple and fixed: a flat 7-day wait after any failure, no escalation. If your state isn’t in this data yet with a confirmed number, the safest assumption is to prepare thoroughly for the first attempt rather than plan around a fast retest.
A fee often comes with the wait
Several states charge a real retest fee, and it isn’t always flat. Kansas’s fee structure changes depending on whether you retest within 6 months of your last attempt. Idaho charges a flat $5 retest fee alongside its 3-day wait. Minnesota doesn’t charge extra for a first or second retake, but adds $10–$20 starting on the third attempt — a real financial incentive to be ready before you walk in, not just to keep trying until something sticks.
How this data was verified
Every row in the table above was researched directly against the issuing state’s own official DMV, DOT, or BMV page as of 2026-09-03 — not pulled from a third-party aggregator. Where a state’s own page didn’t state a fixed wait time, or where two official sources disclosed conflicting information, that’s disclosed honestly in the table rather than resolved by guessing. See each state’s own CDL practice page on this site for the full real fee and CLP-term detail behind this table.