Colorado Following-Distance & Headlight Rules

Use the three-second rule in normal conditions: watch the vehicle ahead pass a fixed reference point (sign, mile marker, utility pole), then count 'one-thousand-one, one-thousand-two, one-thousand-three.' If you pass the reference point before finishing the count, you are following too closely. Increase the following gap in rain, snow, ice, fog, heavy traffic, at night, or on unfamiliar roads, and any time stopping distance is likely to grow. A typical passenger car at 55 mph needs about 200 feet to stop in ideal conditions.

Source: Colorado Driver Handbook (2023), Safe Driving Tips, Three-second rule; Speed, Stopping distance

500

Source: Colorado Driver Handbook (2023), Night Driving

200

Source: Colorado Driver Handbook (2023), Night Driving

Colorado law requires headlights to be on from sunset to sunrise and whenever visibility is less than 1,000 feet. Parking lights alone do not satisfy the requirement. Any vehicle parked alongside the roadway, attended or not, must have its parking lights on during the same conditions. Use low beams and front fog lights, if equipped, to improve visibility in fog or heavy rain; high beams reflect off the moisture and reduce sight distance. Dim high beams within 500 feet of an oncoming vehicle and within 200 feet of a vehicle you are following. Running low beams or daytime running lights at all times is recommended.

Source: Colorado Driver Handbook (2023), Night Driving and Weather sections

The Colorado Driver Handbook does not give a numeric following distance specific to motorcycles. It instructs drivers to use extra caution around motorcyclists and to increase following distance because motorcycles are smaller and harder to see, can stop more quickly than expected, may move within their lane to avoid road defects or debris, and can be moved out of lane by strong winds. The general three-second following rule still applies and should be extended in poor conditions or when following any smaller, less visible road user.

Source: Colorado Driver Handbook (2023), Sharing the Road, Motorcycles; Safe Driving Tips, Three-second rule

Colorado requires drivers to give bicyclists a minimum of three feet of clearance between the outermost part of the vehicle (including mirrors, trailers, or other projections) and the bicyclist when passing or overtaking. The three-foot rule applies on all roadways, whether or not a 'Pass 3 Ft Min' sign is posted. When three feet cannot be given, slow down and stay behind the bicyclist until it is safe to pass. A driver may briefly cross a solid yellow line, including a double solid yellow line, to provide the three feet when there is no oncoming traffic and a clear view ahead. Give more than three feet on rural roads, when driving a larger vehicle, or in windy conditions, because wind blasts from passing vehicles can knock a bicyclist off the bike.

Source: Colorado Driver Handbook (2023), Pavement Markings (yellow lines), Passing, and Bicyclists sections

When you approach any stationary vehicle on the shoulder showing emergency, tow, utility, or plain hazard lights, move over one full lane away if there is a lane in your direction to move into. If there is not, or you cannot move over safely, slow down: 25 mph or less where the speed limit is under 45, and 20 mph below the limit where it is 45 or higher. C.R.S. 42-4-705(2)(a) covers four classes of stationary vehicle: an authorized emergency vehicle (including a port of entry vehicle) showing flashing red, blue, or white lights; a towing carrier vehicle showing flashing yellow lights; a public utility service vehicle (or its authorized contractor) showing flashing amber lights; and, since the 2020 amendment, any stationary motor vehicle giving a hazard signal by displaying alternately flashing lights or warning lights. That last class means the duty is not limited to responders: an ordinary disabled car with its four-way flashers on triggers it. On a highway with at least two lanes going your direction on your side, subsection (2)(b) makes the lane change mandatory, not optional, unless a peace officer directs otherwise or weather, road conditions, or the immediate presence of traffic makes it impossible. If you cannot move over, or the road has only one lane your way, subsection (2)(c) requires a reduced, safe speed, and it fixes presumptively safe numbers: 25 mph or less if the limit is under 45 mph, and 20 mph below the limit if the limit is 45 mph or more. Two related duties sit in the same section: subsection (2.5) applies the same move-over-or-slow-down rule to maintenance, repair, or construction vehicles moving at less than 20 mph, and subsection (2.6) applies it to a vehicle stopped on the side of the highway having chains installed. A violation is careless driving; if it proximately causes bodily injury it is a class 1 misdemeanor traffic offense, and if it causes a death it is a class 6 felony.

Source: C.R.S. 42-4-705(2), Colorado Revised Statutes 2024, Title 42, p. 510: "the driver of an approaching or passing vehicle shall proceed with due care and caution and yield the right-of-way by moving into a lane at least one moving lane apart from the stationary vehicle"; presumed safe speeds at 42-4-705(2)(c)(II), p. 511. Colorado Driver Handbook (2023), p. 25: "you must move over one lane, if you can do so safely." · Verified Aug 2026

The Colorado Driver Handbook teaches defensive driving as a set of habits rather than a named system. Drivers are told to scan ahead, to the sides, and behind every five to eight seconds, to keep a three-second following gap under normal conditions, and to adjust speed to weather, traffic, and road conditions. The book does not adopt a formal acronym such as SIPDE, IPDE, or Smith System.

Source: Colorado Driver Handbook (2023), Safe Driving Tips, p. 18