One-way traffic sign

A rectangular blue or white sign bearing a single arrow, showing the only permitted direction of travel.

Also known as: One way, Arrow sign

Road & transportStandard profile

Meanings

The one-way sign shows the single direction in which a road may be travelled. It is an informative sign rather than a prohibition, which is why it is rectangular rather than a red circle.

Officially standardisedVerified fact
Indicates that the road ahead may be used in the direction of the arrow only.
Contracting parties to the 1968 Vienna Convention · Contexts: Road signage
Officially standardisedVerified fact
Is rectangular because the Convention treats it as an informative sign — it states a fact about the road rather than imposing a prohibition, which would take a red-bordered circle.
Contracting parties to the 1968 Vienna Convention · Contexts: Road signage
Common modern usageVerified fact
Varies in colour by country within the Convention's allowance: a white arrow on blue is common across Europe, while black on white is used elsewhere.
Contexts: Road signage

Visual description

A rectangle wider than it is tall, carrying a single horizontal arrow with a solid triangular head, pointing to the direction of permitted travel.

Symmetry: horizontal
Orientation: upright
Colours: blue, white

Opposite of: No entry sign
The permitted direction, and the forbidden one.

Confidence

IdentityHigh confidence: High confidence because the identity is defined by a current official standard, but multiple independent sources agree.
Historical originModerate confidence: Moderate confidence because the historical origin is documented in encyclopedic references, but multiple independent sources agree, but early or supporting evidence is limited, but the regional or cultural match to this specific claim is not precise.
Current useHigh confidence: High confidence because the current use is defined by a current official standard, but multiple independent sources agree.
Visual matchHigh confidence: High confidence because the visual match is documented in encyclopedic references, but multiple independent sources agree.

Sources

Convention on Road Signs and Signals (Vienna, 8 November 1968), consolidated text
United Nations Economic Commission for Europe · retrieved 2026-07-31
A treaty binding only on its contracting parties. It prescribes sign categories, shapes and colours and permits national variants within them; it does not describe the signage of non-signatory states, notably the United States. Cited for category and design prescription, never for the traffic law of a particular country.
Vienna Convention on Road Signs and Signals
Wikipedia · retrieved 2026-07-31
Tertiary reference. Used for what a sign depicts, which countries use which variant, and the broad regulatory lineage — not for an article number of the treaty or for the law of any single jurisdiction.
One-way traffic
Wikipedia · retrieved 2026-07-31
Tertiary reference. Used for what a sign depicts, which countries use which variant, and the broad regulatory lineage — not for an article number of the treaty or for the law of any single jurisdiction.
Convention on Road Signs and Signals of 1968 and the European Agreement supplementing it
United Nations Economic Commission for Europe · retrieved 2026-07-31
The publisher's own landing page for the consolidated instruments. Used for the status and scope of the Convention and its supplementing agreement rather than for the text of any provision.
Traffic sign
Wikipedia · retrieved 2026-07-31
Tertiary reference. Used for what a sign depicts, which countries use which variant, and the broad regulatory lineage — not for an article number of the treaty or for the law of any single jurisdiction.

Last reviewed 2026-07-31

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Road signs and what their shapes mean

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Meanings

The one-way sign shows the single direction in which a road may be travelled. It is an informative sign rather than a prohibition, which is why it is rectangular rather than a red circle.

Officially standardisedVerified fact

Indicates that the road ahead may be used in the direction of the arrow only.

Contracting parties to the 1968 Vienna Convention · Contexts: Road signage

Officially standardisedVerified fact

Is rectangular because the Convention treats it as an informative sign — it states a fact about the road rather than imposing a prohibition, which would take a red-bordered circle.

Contracting parties to the 1968 Vienna Convention · Contexts: Road signage

Common modern usageVerified fact

Varies in colour by country within the Convention's allowance: a white arrow on blue is common across Europe, while black on white is used elsewhere.

Contexts: Road signage

Confidence

IdentityHigh confidence: High confidence because the identity is defined by a current official standard, but multiple independent sources agree.
Historical originModerate confidence: Moderate confidence because the historical origin is documented in encyclopedic references, but multiple independent sources agree, but early or supporting evidence is limited, but the regional or cultural match to this specific claim is not precise.
Current useHigh confidence: High confidence because the current use is defined by a current official standard, but multiple independent sources agree.
Visual matchHigh confidence: High confidence because the visual match is documented in encyclopedic references, but multiple independent sources agree.

Sources

Convention on Road Signs and Signals (Vienna, 8 November 1968), consolidated text
United Nations Economic Commission for Europe · retrieved 2026-07-31
A treaty binding only on its contracting parties. It prescribes sign categories, shapes and colours and permits national variants within them; it does not describe the signage of non-signatory states, notably the United States. Cited for category and design prescription, never for the traffic law of a particular country.
Vienna Convention on Road Signs and Signals
Wikipedia · retrieved 2026-07-31
Tertiary reference. Used for what a sign depicts, which countries use which variant, and the broad regulatory lineage — not for an article number of the treaty or for the law of any single jurisdiction.
One-way traffic
Wikipedia · retrieved 2026-07-31
Tertiary reference. Used for what a sign depicts, which countries use which variant, and the broad regulatory lineage — not for an article number of the treaty or for the law of any single jurisdiction.
Convention on Road Signs and Signals of 1968 and the European Agreement supplementing it
United Nations Economic Commission for Europe · retrieved 2026-07-31
The publisher's own landing page for the consolidated instruments. Used for the status and scope of the Convention and its supplementing agreement rather than for the text of any provision.
Traffic sign
Wikipedia · retrieved 2026-07-31
Tertiary reference. Used for what a sign depicts, which countries use which variant, and the broad regulatory lineage — not for an article number of the treaty or for the law of any single jurisdiction.

Last reviewed 2026-07-31

Meanings

Visual description

Related & commonly confused symbols

Meanings

Visual description

Related & commonly confused symbols