Are drivers required to follow temporary diversion signs in Northern Ireland?

Drivers should follow signed temporary diversions in Northern Ireland when the normal route is closed or restricted.

This is a specifically Northern Ireland question because the applicable road rules, DfI/DVA processes and Northern Ireland Highway Code are the relevant reference point. The closure itself may be legally enforceable, while diversion signs direct traffic around it. A sat-nav route through the closed road does not override temporary traffic management.

For this exact issue — “Are drivers required to follow temporary diversion signs in Northern Ireland?” — check the live temporary signs first, then confirm the works entry on TrafficWatchNI if you need dates, diversion details or the organisation responsible. Temporary traffic management can alter the normal lane layout, speed limit, access or priority, so an old sat-nav route or memory of the road is not reliable evidence of what is permitted today.

Continue to obey all permanent restrictions on the diversion, including weight, height, one-way and speed controls. If the diversion becomes unsafe or blocked, find a lawful alternative rather than bypassing closure barriers. If signs, licence categories, vehicle plates or official instructions conflict with something remembered from an older guide, follow the current official information and the live road signs.

Before publishing this answer, the key factual point in “Are drivers required to follow temporary diversion signs in Northern Ireland?” was checked against current Northern Ireland official guidance. That matters because road rules, licence entitlements and enforcement details can differ from Great Britain and can change over time; the sources attached below are the ones to re-check if the rule is updated.