Knowledge base Road rules Updated 21 Oct 2026 9 min read

Keep left and overtaking

Highway Code keep-left, lane-discipline, and overtaking rules, including when you may pass on the left, where you must not overtake, current SPF handbook cautions against unsafe overtaking, and the official handbook’s road-hogging note.

keep-left overtaking lane-discipline Highway-Code

Primary source: https://sso.agc.gov.sg/SL/RTA1961-R11?ProvIds=P1IV-

Statutory left-side driving and passing

Rule 3 of the Road Traffic Rules says every vehicle must ordinarily be driven on the part of the road between its centre and the left-hand edge. When overtaking, except where the Rules specifically provide otherwise, the driver must pass so the vehicle being overtaken is on the driver's left or near side, and must avoid causing inconvenience or danger. Rule 4 provides one specific exception: if the driver ahead signals and takes the position required by rule 7 for a turn, the overtaking driver may pass on either side (Singapore Statutes Online, current Road Traffic Rules, rr. 3, 4 and 7).

When driving along, do not hog the middle of the road. Keep well to the left and as near as practicable to the edge of the road (including on dual carriageways) unless you intend to overtake, you intend to turn right, or there is a full-day bicycle lane (keep to the left-most vehicle lane at any time) or a part-day bicycle lane (keep to the left-most vehicle lane during its operating hours) (SSO, Highway Code r 50).

Do not drive, stop or park on a full-day bicycle lane at any time, or on a part-day bicycle lane during its operating hours (SSO, Highway Code r 49A).

You must not cross the centre line at bends, near the crest of a rise, or anywhere else where you cannot clearly see the road ahead (SSO, Highway Code r 51).

Lane discipline

You must obey arrows or words marked in the lanes. You must not change lanes so suddenly as to inconvenience or endanger other traffic. Signal early before changing lanes (SSO, Highway Code r 55).

In traffic hold-ups, do not “jump the queue”. Well before a junction, make sure you are in the appropriate lane (SSO, Highway Code rr 56–57).

On a two-lane carriageway, keep to the left-hand lane except when overtaking. On a three-lane carriageway, you may keep to the central lane when the left-hand lane is occupied by slower moving vehicles. The outer (right-hand) lane is for overtaking only; do not stay in it longer than necessary after overtaking vehicles in the centre lane (SSO, Highway Code rr 58–59).

OneMotoring’s informative “keep to the left” sign caption is: right lanes are for overtaking only (OneMotoring, Driving Rules and Information).

Drivers of large vehicles must always keep such vehicles to the road or vehicle speed limit (whichever is lower) and travel on the extreme left lane of the road (except for bus lanes during their operating hours) to allow faster vehicles to overtake on the right (SSO, Highway Code r 101).

Overtaking

Never overtake unless you can do so without danger to yourself or others. Be specially careful at night, and in heavy rain and mist (SSO, Highway Code r 60).

The SPF Basic Theory of Driving handbook illustrates a 12-step overtaking sequence: check traffic ahead and behind, signal right, check the blind spot, move right and accelerate to pass, sound the horn if necessary, check the mirror, signal left, move back left, cancel the signal, and resume normal speed (SPF, Basic Theory of Driving).

The current SPF Final Theory of Driving handbook adds three cautions: overtake no more than one vehicle at a time; do not persist if the vehicle ahead suddenly increases speed; and do not overtake when the forward view is restricted or obscured (SPF, Final Theory of Driving handbook, p. 58).

The “overtaking on the right” rule does not apply when the driver in front has signalled an intention to turn right (you can overtake on the left); when you are filtering to the left before a junction; or when there is slow-moving congested traffic and the vehicles on your right are moving more slowly than your vehicle (SSO, Highway Code r 61).

Return to the appropriate lane as soon as practicable after overtaking, but do not cut in sharply (SSO, Highway Code r 62).

Do not overtake when you are at, or approaching, a pedestrian crossing, a road junction, a corner or bend, the brow of a hill, or a double white line (SSO, Highway Code r 63). Do not overtake where the road narrows, if it would force another vehicle to swerve or reduce speed, or if in doubt (SSO, Highway Code r 64).

When being overtaken, never increase speed to prevent another driver from passing (SSO, Highway Code r 65).

Where continuous double white lines separate opposite flows, you may not overtake at those lines unless you keep entirely to the left of them. Never cross double white lines; making a U-turn or right turn is also not allowed on a road where those lines are painted (SSO, Highway Code rr 52–53).

Road-hogging (official handbook)

The official handbook states that road-hogging is driving at an unreasonably slow speed especially on the right-hand or along the centre of the road, which hinders traffic behind and may cause others to pass dangerously on the left. Motorists who travel at a slow speed should keep to the left; this applies especially to small-capacity motorcycles, goods vehicles and lorries. You should only use the right-hand lane when overtaking or when about to turn right or make a U-turn (SPF, Basic Theory of Driving).

Traffic Police’s composition table lists “vehicles with a 60 km/h vehicular speed limit failing to keep left” with no demerit points in that row and $100 / $150 composition (light / heavy) (SPF, Penalties for Traffic Offences). Crossing double white lines or a road divider is listed as 4 demerit points and $150 / $200 (SPF, Penalties for Traffic Offences). Separately, the current Driver Improvement Points System Schedule lists “obstructing flow of traffic” as a 4-point offence under rule 5 of the Road Traffic Rules, whose heading is “Vehicle to keep close to left-hand edge of roadway”; SPF’s composition table lists that obstruction offence in its 4-point row with $150 / $200 composition for light / heavy vehicles (SSO, DIPS Rules, Schedule, item 17; SSO, Road Traffic Rules, r 5; SPF, Penalties for Traffic Offences). The official pages do not state a specific factual threshold for when conduct amounts to this obstruction offence; do not infer that every instance of driving in a right lane automatically attracts it.

Coverage debt

The official sources map the 4-point “obstructing flow of traffic” offence to Road Traffic Rules r 5, but do not state a specific factual threshold for when conduct amounts to that offence. Do not infer that every instance of driving in a right lane automatically attracts it.
Following-distance rule (one car length per 16 km/h) is Highway Code r 67 and is not expanded here.
The SPF Basic Theory of Driving handbook also describes one-way streets (but not dual carriageways) as a situation where vehicles may pass on either side. Current Highway Code r 61 lists three exceptions to overtaking on the right and does not include this one-way-street wording. The article reports the current Code exceptions; the difference between the Code and handbook wording remains unresolved (SPF, Basic Theory of Driving; SSO, Highway Code r 61).