Idaho Road Signs: 40-Question ITD Test, Open Range & School Bus Rules

How many questions are on the Idaho knowledge test and how many can you miss? What is the fee for the Idaho knowledge test? When are you not required to stop for a school bus on a 4-lane highway in Idaho? The Idaho Transportation Department at dmv.idaho.gov gives a 40-question test. miss up to 6. The test fee is $5. On a 4-lane highway divided by a median, only traffic behind the bus must stop. Railroad stops are within 50 feet max, 15 feet minimum.

Table of Contents

1. Idaho "Reasonable and Prudent" Speed Law and Why the 40-Question Knowledge Test Demands Full Prep

Idaho roads stretch from Boise urban grid and Nampas commercial corridors to the Snake River Canyon near Twin Falls, the Rocky Mountain passes above Idaho Falls and Pocatello, and the forested Panhandle highways near Coeur dAlene. The Idaho Transportation Department (ITD) knowledge test consists of 40 questions, you may miss up to 6 to pass. The test fee is $5.00 (no checks accepted). Retest fees are the same as original fees. Study the current Idaho Drivers Handbook (July 2024) at dmv.idaho.gov. Idaho basic speed law requires driving at a speed that is "reasonable and prudent at all times", even below the posted limit when conditions demand it.

2. Identify Any Idaho Road Sign Before the Text: Shape and Color on the ITD Knowledge Exam

On Idaho high-speed interstates, blind mountain curves, and open Snake River Plain highways, you must read a signs shape and color before the text is legible. The Idaho ITD knowledge test specifically includes sign identification questions. master shape and color before your $5 test appointment.

Shape	Diagram	Meaning	Example Sign
Octagon (8-sided)		STOP. always and only
Triangle (inverted)		Yield to other traffic
Diamond		Warning - hazard ahead
Rectangle (vertical)		Regulatory - rules of the road
Rectangle (horizontal)		Guide or informational
Pentagon (5-sided)		School zone or crossing - exclusively
Round (circle)		Railroad crossing advance warning - exclusively
Pennant		No passing zone - exclusively
Orange (any shape)		Construction and work zone warnings
Blue (any shape)		Motorist services - gas, food, lodging, hospitals
Brown (any shape)		Recreation areas, parks, and scenic routes

3. Idaho Regulatory Signs: Moving Violations Under Idaho Point System and License Suspension Rules

Regulatory signs in Idaho are legally binding. disobeying them is a moving violation that adds points under Idaho suspension and point violations system. Accumulate 12 or more points in 12 months and face a 30-day suspension; 24+ points in 36 months means a 6-month suspension. White rectangular signs, prohibitory signs, and lane-control signs are all tested on the Idaho knowledge exam.

STOP Sign

Come to a full stop; yield to all traffic and pedestrians before proceeding

YIELD Sign

Slow down and give right-of-way to cross traffic or pedestrians

Speed Limit Sign

Maximum legal speed under ideal conditions

Do Not Enter Sign

You are going the wrong way; do not proceed

Wrong Way Sign

You have entered a one-way road going against traffic

No U-Turn Sign

U-turns are prohibited at this location

No Left Turn Sign

Left turns are not allowed

No Right Turn Sign

Right turns are not allowed

One Way Sign

Traffic moves in one direction only

Keep Right Sign

Stay to the right of an island or obstruction

No Passing Zone Sign

Passing is forbidden in this stretch. pennant-shaped sign

Do Not Pass Sign

Passing prohibited. do not overtake vehicles ahead

No Turn on Red Sign

No turns permitted on a red light at this intersection

No Left Turn on Red Sign

Left turn on red is prohibited here

No Right Turn on Red Sign

Right turn on red is prohibited here

Turn Left Only Sign

You must turn left from this lane

Turn Right Only Sign

You must turn right from this lane

Straight or Turn Right Sign

You may go straight or turn right from this lane

Minimum Speed Limit Sign

You must drive at least this speed on this road

Slower Traffic Keep Right Sign

Slower vehicles must use the right lane

No Parking Sign

Parking is prohibited in this area

No Trucks Sign

Commercial trucks are prohibited on this road

No Bicycles Sign

Bicycles are not permitted on this road

No Pedestrian Crossing Sign

Pedestrians must not cross here

Reserved Parking Sign

Parking reserved for designated users (e.g., accessible parking)

Four Way Stop Sign

All four directions must stop at this intersection

Stop Except Right Turn Sign

All traffic must stop except those turning right

Left Turn Yield on Green Sign

Left-turning vehicles must yield to oncoming traffic on green

Lane Use Control Sign

Indicates which movements are permitted or prohibited from a specific lane

Restricted Lane Ahead Sign

An upcoming lane has restrictions on who may use it

4. Idaho Warning Signs: Hazards on Open Range Roads, Mountain Passes & Snake River Canyon Approaches

Diamond-shaped warning signs flag hazards before you reach them. on Idaho roads that means open range livestock crossings, steep mountain grades in the Sawtooth and Bitterroot ranges, blind curves on Panhandle roads, and wildlife corridors statewide. Orange signs mark active work zones where enhanced fines apply when posted. Idaho open range law means livestock have the right-of-way. hitting an animal on open range makes the driver liable, not the owner.

Left Curve

A curve to the left is ahead; reduce speed

Right Curve

A curve to the right is ahead; reduce speed

Sharp Left Turn

A very sharp left turn is coming; slow down significantly

Sharp Right Turn

A very sharp right turn is coming; slow down significantly

Winding Road

Series of curves ahead

Set of Curves (Left-Right)

Multiple curves ahead, first curving left then right

Set of Curves (Right-Left)

Multiple curves ahead, first curving right then left

Sharp Turns (Left-Right)

Successive sharp turns ahead. left then right

Slippery When Wet

Road surface becomes slick in rain; reduce speed

Deer Crossing

Wildlife frequently cross here. deer, elk, and moose are active hazards on Idaho mountain highways and open range roads statewide

Pedestrian Crossing

Crosswalk ahead; watch for foot traffic

Bicycle Crossing

Cyclists frequently cross here; slow down and yield to bikes

School Zone / Crossing

Children may be present. obey posted Idaho school zone speed limits; there are increased penalties for speeding violations in school zones

School Crossing Ahead

A school crosswalk is approaching; watch for children and crossing guards

Divided Highway Begins

Road splits into two one-way sections; keep right

Divided Highway Ends

Two-way traffic resumes

Merging Traffic

Another lane of traffic is joining yours

Added Lane

A new lane is being added ahead. merging traffic does not need to yield

Lane Ends Ahead

Your lane ends ahead. merge safely into the adjacent lane

Lane Ends Merge Left

Your lane ends. move to the left lane

Left Lane Ends

The left lane ends ahead. merge right

Road Narrows

The road becomes narrower ahead; stay alert

Narrow Bridge Ahead

Bridge ahead is narrower than the road. proceed carefully

Low Clearance

Bridge or overhead obstruction with limited height clearance

Railroad Crossing (RR)

Tracks ahead; look and listen for trains

Hill / Steep Grade (Downgrade)

Downgrade ahead; trucks should check brakes

Bump

A raised bump or speed hump is ahead; slow down

Dip

A dip in the road is ahead; reduce speed

Loose Gravel

Road surface has loose gravel. reduce speed and increase following distance

Pavement Ends

Paved road ends ahead; expect gravel or dirt surface

Shoulder Drop Off

Road shoulder drops off steeply. avoid driving on the edge

Watch for Ice on Bridges

Bridges freeze before road surfaces. reduce speed in cold weather

Two Way Traffic Ahead

Divided road ends. two-way traffic begins ahead

Cross Road

An intersection with a crossing road is ahead

Cross Traffic

Traffic crosses your path ahead. be prepared to yield

T Intersection

The road ends at a T. you must turn left or right

Side Road

A side road enters the highway ahead at an angle

Highway Intersection Ahead

A highway intersection is approaching; be prepared to yield or stop

Road Entering Curve

A road enters from the side on a curve ahead. watch for merging traffic

Roundabout

A roundabout is ahead. yield to circulating traffic and travel counterclockwise

Truck Rollover

High risk of truck rollover on this curve or ramp. trucks reduce speed significantly

Weave Area

Traffic is entering and exiting simultaneously. expect lane changes and merging

Advisory Speed

Recommended safe speed for a curve or hazard. not legally enforced but strongly advised

Traffic Signal Ahead

A traffic light is ahead. be prepared to stop

5. Idaho Guide & Informational Signs: Navigating I-84, I-86, US-93 & Idaho 511 Traveler Services

Guide signs do not regulate driving. they show destinations, distances, and services. Green = highway navigation. Blue = motorist services. Brown = parks and recreation. Idaho 511 Traveler Services (dial 511 or visit 511.idaho.gov) provides real-time road conditions, closures, and weather information statewide.

Interstate Route Marker

Identifies the interstate number (e.g., I-84, I-86, I-15, I-90)

US Route Marker

Marks US highways (e.g., US-20, US-26, US-93 Sawtooth Scenic Route)

State Route Marker

Identifies Idaho state highways (e.g., ID-21 Ponderosa Pine Scenic Byway, ID-55 Horseshoe Bend Hill)

Exit Sign (Exit Only)

Shows upcoming freeway exit and distance

Mile Marker

Indicates distance from the state line or route origin

Services Sign

Points to nearby gas, food, lodging, or medical facilities

Hospital Sign (H)

Indicates direction to the nearest hospital

Diesel

Indicates diesel fuel is available at the next service area

Park / Recreation Sign

Directs to state parks, campsites, and scenic areas

6. Idaho Traffic Signals: Power Outages, Arrow Phases & What the ITD 40-Question Exam Tests

Flashing red = stop sign. Flashing yellow = yield. The Idaho knowledge test covers all signal types. and specifically tests what to do when traffic signals are not functioning due to a power outage: treat the intersection as a four-way stop.

Standard Traffic Lights

Steady Red

Come to a complete stop behind the stop line. Wait until green.

Steady Yellow

Prepare to stop. the light is about to turn red. Do not speed up to beat it.

Steady Green

Proceed if the intersection is clear. You must still yield to pedestrians and cross traffic.

Green Arrow (left)

You may proceed only in the direction of the arrow. Oncoming traffic is stopped.

Yellow Arrow (no left)

The protected turn is ending. Prepare to stop or yield if you have not yet entered the intersection.

Red Arrow (no left)

Do not turn in the direction of the arrow. Wait for a green arrow or green light.

Green. no left arrow

Proceed straight or right. left turn not permitted on this phase.

Opposing Traffic Extended Green

Oncoming traffic has an extended green phase. wait before turning left.

Flashing Signals

Flashing Red

Treat as a STOP sign, come to a complete stop, then proceed when safe.

Flashing Yellow

Treat as a YIELD sign, slow down, look carefully, and proceed with caution.

Flashing Red Beacon

Overhead flashing red beacon. treat as a stop sign. Come to a full stop, then proceed when safe.

Flashing Green Arrow

You may turn in the direction of the arrow after yielding to oncoming traffic and pedestrians.

Pedestrian Signals

WALK / White Walking Figure & DONT WALK / Orange Hand

White walking figure = pedestrians may cross. Orange hand = do not start crossing; if already crossing, finish quickly.

Flashing Orange Hand + Countdown

Crossing phase is ending. Pedestrians who have started may finish; others should not begin.

Key test point: Flashing red = stop sign. Flashing yellow = yield. When traffic signals are not functioning due to a power outage, treat the intersection as a four-way stop. All three rules appear on the Idaho ITD knowledge exam.

7. Idaho Pavement Markings: Dashed Yellow Lines, Shared Center Turn Lanes & Edge Lines

Yellow lines separate opposing traffic. White lines separate same-direction traffic. The Idaho knowledge test covers lane lines, road arrows, curb markings, and pavement symbols. including Idaho shared center turn lane rules and the dashed bike lane line rules at intersections.

Line Colors

Yellow lines

Separate traffic moving in opposite directions

White lines

Separate traffic moving in the same direction, or mark the edge of the road

Line Types

Broken yellow line (Single)

Passing allowed when safe on your side

Solid yellow + broken yellow

Passing allowed only on the broken-line side

Double solid yellow lines

No passing in either direction

Broken white line

Lane changes permitted when safe

Solid white line

Do not cross. lane edge, crosswalk, or stop line

Double solid white lines

Do not change lanes. often used near intersections or toll areas

Center Turn Lane

Shared left-turn lane. used to begin or complete a left turn only

Center Turning Lane (sign)

Overhead or posted sign marking a shared center left-turn lane

Pavement Symbols & Special Markings

Arrows in lane

Indicate which direction(s) you may travel from that lane

Stop line (wide white bar)

Stop your vehicle completely behind this line at red lights and stop signs

Stop Here on Red

Painted instruction on pavement. stop at this marked line on red

Crosswalk lines

Mark the pedestrian crossing area. yield to pedestrians within these lines

Broken white line (pavement)

Lane changes permitted when safe

Solid white line (pavement)

Do not cross. lane edge, crosswalk, or stop line

Double solid white lines (pavement)

Do not change lanes. often used near intersections or toll areas

Railroad crossing markings (X + RR)

Advance warning of tracks ahead. painted on pavement before the crossing

Diagonal yellow lines (gore area)

Do not drive in this area. marks a traffic island or diverging zone

Bicycle lane marking

White painted lane reserved for cyclists. do not drive or park in it

HOV / Carpool lane diamond

Lane restricted to vehicles with 2 or more occupants during posted hours

Yellow curb

No parking or stopping at any time

Red curb

No stopping, standing, or parking. fire zone

White curb

Passenger loading/unloading only. brief stops permitted

Key test point: Yellow lines always separate opposing traffic. White lines always separate same-direction traffic. This is a foundational rule that appears on nearly every DMV exam.

8. Idaho Work Zone Signs: Enhanced Penalties, Slow-Moving Equipment & ITD Construction Zones

Orange signs with black lettering mark active construction and maintenance work zones on Idaho roads. When signs indicate enhanced fines are in effect, fines for speeding violations are increased in designated work zones. School safety patrols, flaggers, and law enforcement officers may all direct traffic through Idaho work zones and must be obeyed immediately.

Road Work Ahead

Construction zone begins ahead. reduce speed and be alert

Flagger Ahead

A person is directing traffic. obey their signals immediately

Workers Ahead

Road workers are present. slow down and be prepared to stop

Active Work Zone

You are in an active work zone. fines doubled, drive with extra caution

End of Active Work Zone

Work zone ends. normal speed and rules resume

Work Zone Headlights

Headlights required in this work zone

Lane Closed Ahead

A travel lane ends ahead. merge early and do not pass in the closed lane

Road Closed

Road is completely closed. do not enter, follow detour signs

Orange barrels / cones

Mark lane boundaries and closures in active work zones

Channelizing devices (barricades)

Direct traffic around obstacles or closed areas

• You must obey a flaggers directions even if they conflict with existing signs or signals.
• When work zone signage indicates enhanced penalties, fines for speeding violations are increased in that designated zone.
• Watch for slow-moving vehicles and farm equipment in Idaho work zones and on rural highways. the orange triangular slow-moving vehicle emblem means the vehicle travels at 25 mph or less.
• Move over and reduce speed for emergency vehicles, tow trucks, and highway maintenance vehicles stopped with lights flashing. Idaho Move Over law (AS 28.35.185) requires this.
• Never drive through or around a closed lane barrier. follow flagger directions or posted detour signs.

Key test point: Orange always means construction or work zone. If you see orange, reduce speed and increase following distance immediately.

9. Railroad Crossings in Idaho: The 50-Foot and 15-Foot Stop Rules Tested on the Knowledge Exam

When approaching a railroad grade crossing in Idaho, you must stop within 50 feet but no less than 15 feet from the nearest rail when required. This specific distance range is included in Idaho practice test questions and is directly tested on the knowledge exam. Never shift gears on the crossing. you might stall.

Advance Warning Sign

Railroad crossing ahead. the first sign you see. Begin slowing down.

RR Crossbuck Sign (X-shaped)

Located at the crossing itself. yield to trains. Treat as a yield sign if no gates or lights.

Railroad Crossing (at crossing)

Marks the exact railroad crossing location

Crossing Gates

Lower when a train is coming. never drive around or under a lowered gate

Pavement markings (X + RR)

Painted on the road surface before the crossing as an advance warning

Flashing Red Lights

A train is approaching, stop and wait. Do not proceed until lights stop and it is fully clear.

Stop Line

Idaho requires stopping within 50 feet but no less than 15 feet from the nearest rail when required at a crossing

• The round yellow advance warning sign is always the first sign you see approaching a railroad crossing.
• Stop within 50 feet but no less than 15 feet from the nearest rail when required. this exact range is tested in Idaho practice exam questions.
• Never shift gears when crossing railroad tracks. stalling on the tracks is extremely dangerous.
• Never stop on the tracks. ensure there is room on the far side before proceeding across.
• Never drive around or under a lowered crossing gate. it is illegal in Idaho.
• Watch for a second train after one passes. do not proceed until you are sure no train is approaching on another track.
• School buses, vehicles carrying hazardous materials, and transit buses must stop at all railroad crossings.

Key test point: Idaho railroad stop rule, within 50 feet but no less than 15 feet from the nearest rail. is included in Idaho official practice test (Question 18). Know both the minimum and maximum distances.

10. Idaho School Zone Speed Limits and School Bus Stop Rules: What the Practice Test Actually Asks

Pentagon-shaped, fluorescent yellow-green signs mark school zones exclusively. Idaho sets increased penalties for speeding violations in school zones. posted signage indicates when enhanced fines apply. Idaho school bus stop rules are directly tested in the official practice exam. Question 4 asks exactly when you are not required to stop.

School Zone

School ahead. be alert for children, reduce speed

School Speed Limit

Obey posted Idaho school zone speed limits. there are increased penalties for speeding violations in school zones when signage indicates

Speed Limit Lights Flashing

Speed limit applies only when the flashing lights are active

School Crossing Ahead

Crosswalk used by schoolchildren ahead. yield to crossing guard and students

• Idaho sets increased penalties for speeding violations in school zones. posted signs indicate when enhanced fines are in effect.
• You must stop for a school bus when the red lights near the top of the bus are flashing and/or the stop arm on the left side is extended. remain stopped until all children are clear of the roadway and the bus resumes motion.
• Traffic must stop when approaching a school bus that has stopped to pick up or drop off children.
• You do not have to stop if you are traveling in the opposite direction on a highway with four or more lanes where two lanes are going in each direction. this is Idaho Practice Test Question 4.
• Always obey school safety patrol officials. they are appointed by the school, wear appropriate insignia marked "School Patrol," and display STOP signs at school crossings. You must follow their directions.
• Slow down and watch carefully in school zones. children are often unpredictable pedestrians and difficult to see.

Key test point: The pentagon shape is used exclusively for school signs. No other sign category uses this shape. making it one of the easiest shapes to identify on the exam.

11. Pedestrian & Bike Signs in Idaho: Sharing Mountain Roads, Bike Lane Rules & Open Range Awareness

Pedestrians have right-of-way at all crosswalks. marked or unmarked. Idaho requires motorists to pass bicyclists with a safe clearance of at least 3 feet. Bicyclists in Idaho do not need to come to a complete stop at stop signs but must yield to vehicles already at or in the intersection. Both sign types use fluorescent yellow-green and are covered on the Idaho knowledge exam.

Pedestrian Crossing Sign

A marked crosswalk is ahead. watch for pedestrians crossing

Bicycle Crossing Sign

Cyclists frequently cross here. reduce speed and yield to bikes

No Bicycles

Bicycles are prohibited on this road or path

No Pedestrian Crossing

Pedestrians must not cross here

• Pedestrians always have the right-of-way in marked crosswalks. stop or slow as necessary when pedestrians are crossing or about to cross.
• Pass bicyclists with a safe clearance. move into the left lane if possible; if not, allow at least 3 feet of space. Wait for a break in oncoming traffic if needed on two-lane roads.
• Idaho law allows bicyclists to proceed through a red light after stopping and yielding to vehicles already in or approaching the intersection. they do not need to come to a complete stop at stop signs, but must yield right-of-way.
• Dashed bike lane lines at intersections indicate a merging movement. when turning right, you may enter the bike lane in the dashed area. Yield to any bicyclist already there.
• Fluorescent yellow-green is used for both school and pedestrian/bike signs. the shape distinguishes between them.

Key test point: Pedestrians always have right-of-way at crosswalks. marked or unmarked. This rule appears on virtually every state DMV exam.

12. How to Score 34/40 on Idaho ITD Knowledge Exam: Signs & Key Laws

• 40 questions, miss up to 6. The Idaho knowledge test has 40 questions. you may miss no more than 6 to pass. The fee is $5.00 (cash only, no checks). If you fail, the retest fee is the same. Schedule at your county DMV office.
• Know Idaho basic speed law word for word. Idaho basic rule requires driving at a speed that is "reasonable and prudent at all times", even below the posted limit in poor conditions. Practice Test Question 13 tests this exact rule.
• Idaho speed limits. Max on interstates: 75 mph (80 where posted). State highways: 65 mph (70 where posted). Residential/business/urban districts: 35 mph unless otherwise posted. Driving too slowly and impeding traffic is also a violation.
• School bus: know the 4-lane exception. You do NOT have to stop for a school bus if you are traveling in the opposite direction on a highway with four or more lanes where two lanes go in each direction. Practice Test Question 4.
• Railroad: 50 feet max, 15 feet minimum. Stop within 50 feet but no less than 15 feet from the nearest rail. Practice Test Question 18. Both distances are tested.
• Power outage = four-way stop. When traffic signals are not functioning due to a power outage, treat the intersection as a four-way stop. Practice Test Question 7.
• Passing on the right. Legal only when the vehicle ahead on a two-lane road is signaling to turn left, or on a one-way or multi-lane road. Practice Test Question 2.
• Bicyclists have unique Idaho rules. They may proceed through red lights after stopping and yielding, and through stop signs after yielding. without coming to a complete stop.
• Open range means livestock have right-of-way. Outside city limits, livestock may roam freely. If you strike an animal on open range and are found negligent, you may be liable for the animals injuries or death.
• Use Idaho 511 Traveler Services. Dial 511 or visit 511.idaho.gov for real-time road conditions, closures, and mountain pass weather before any trip on Idaho highways.

Idaho ITD DMV Driver License