Idaho Road Signs and Their Meanings

Idaho prints the shape of its written exam where you can go and check it. Under the heading Knowledge Test: Class D (Non-Commercial), the Idaho Driver's Handbook says the test "consists of 40 questions; you can miss up to six (6) questions before failing the test," and it says where the material comes from in the same breath: "Knowledge test questions are taken directly from information included in the Driver's Handbook." Licensing belongs to the Idaho Transportation Department's Division of Motor Vehicles — the Idaho DMV — while the testing itself happens locally, at a county driver's license office, and the handbook's fee table puts $5.00 on the knowledge test. What the department has not published anywhere is a breakdown by subject. Neither the handbook nor ITD's Taking the Driver's Test guide says how many of those forty items will put a sign in front of you. So the honest answer to how many signs are on the Idaho test is that the state gives you the total, the margin for error and the source, and then stops.

There is no separate sign score to clear. Six wrong is six wrong in Idaho whether the misses were signs, right-of-way or blood-alcohol limits, and nothing in the handbook or in ITD's testing guide sets aside a portion of the forty for sign identification or requires you to name a minimum number of signs before the rest of your answers count. The closest thing Idaho publishes to a proportion is not the exam at all. The handbook closes with a set of Practice Test Questions — twenty of them, and three of the twenty print a picture and ask what the sign means. Its answer key is not at the back with them; it is near the front of the book, on page 11, more than a hundred pages ahead of the questions it answers. Take that set as the department showing you the format rather than quoting you a ratio, because nothing in the book claims the practice items were built to the same recipe as the real ones. ITD is explicit about the gap, in the knowledge-test section itself: "Web-based driver practice tests are not an accurate representation of Idaho knowledge tests, with the exception of the sample test questions provided by ITD through the itd.idaho.gov website." That is the department drawing a line around its own materials, and it is worth reading before you decide how much weight to put on anybody's practice questions, this site's included.

The book is the Idaho Driver's Handbook, published by the Idaho Transportation Department's Division of Motor Vehicles and dated July 2026 on its opening page — the same page that carries a caveat worth holding on to while you study: "The Idaho Driver's Handbook paraphrases the language of Idaho statutes. Courts go by the actual language of the statutes, not this text." Signs sit inside the chapter called Highway & Vehicle Knowledge, which opens at page 44 on a section titled Signs, Signals, & Pavement Markings. Its first paragraph widens the subject before narrowing it: "Traffic control devices include traffic signals, signs, and pavement markings. Traffic control may also be provided by law enforcement officers, highway personnel, or school crossing guards. You must obey these directions." The named parts that follow are Traffic Signs, Turn Prohibition & Lane Control Signs, Work Zone Signs, School Safety Patrols, Warning Signs, Guide Signs, Barricades, Traffic Signals, Pedestrian Crossings, Pavement Markings and Intersections. Two entries in that list are worth a second look. School Safety Patrols is a person rather than a sign, filed among the sign families because a patrol official displaying a STOP sign at a school crossing is, in Idaho's telling, one more traffic control device you must obey. And the turn-prohibition part is handed over to the signs themselves — Idaho prints them with no paragraph of explanation attached, so arrows and slashes have to carry the whole meaning. Warning Signs gets the longest run of any of the sign parts, four pages of it, starting from the standard shape and color — "Most warning signs are black on yellow and diamond-shaped. They also include the fluorescent yellow/green school warning signs" — and working through Open Range, added lanes, low clearance and the Emergency Notification System sign posted at railroad crossings. Guide Signs is the opposite: a single sentence of rule and then pictures. That sentence is the entire system in a line, though — white on green for direction and distance, white on blue for motorist's services, white on brown for cultural, historical or scenic points of interest.

The published Idaho sign questions here were written from that chapter and only from that chapter — not from the Practice Test Questions at the back of the handbook, and not from ITD's online sample test. Both of those are the department's own material and worth working through on their own terms; nothing on this page is lifted out of either. Each question carries a citation naming the part of the handbook it came from, which makes the weighting visible instead of leaving you to guess at it. Warning Signs carries the most, which tracks the way the handbook itself spends its pages. Guide Signs and Work Zone Signs each carry a share, and so does Barricades — a heading Idaho keeps standing on its own rather than folding into the work-zone pages, which is where most drivers would expect to meet a barricade in the first place. That separation is worth knowing before you plan your reading. A question about the V-shaped pattern that means the road is closed and traffic can go no further, or about lines angling down toward the side you are meant to pass on, sends you to the barricade heading and not to the work-zone advice just before it. Traffic Signs, the opening part where the regulatory shapes and colors are laid out, carries the smallest share of the citations, largely because Idaho keeps that part short and hands the detail to everything after it.

16 published Idaho road-sign questions, each with an explanation and a citation to the handbook section it came from.

Content reviewed against official driver handbooks · August 12, 2026