Today marks the 20th anniversary of the metrication of speed limits in the Republic of Ireland. 20 January 2005 was the day that all speed limits in Ireland switched from mph to km/h.

The following summary of events is reproduced from our main website:

The Republic of Ireland’s metrication programme started much later than that of the UK. However by completing the metrication of its roads in January 2005, it has left the UK well behind.

In contrast to Canada, which started its conversion programme with speed limits, Ireland made changes of speed limits the final stage in the changeover.

Ireland replaced imperial distance signage over a period of 10 years. Since the lifetime of most road signs is also 10 years this meant that there was virtually no cost to this conversion.

The final stage of the programme was to convert the speed limits on 20 January 2005. The Irish Department of Transport took the opportunity afforded by metric conversion to comprehensively review speed limits. As a result, the speed limits should be better tuned to local traffic conditions and hence helping road safety.

The key to a successful changeover was believed to be a very rapid conversion of the actual signs preceded by a blitz of information and publicity in the two weeks preceding the change. Drivers were therefore left in no doubt as to what was happening and were warned that ignorance or confusion about the new limits would not be accepted by the police as an excuse for breaking the new limits.

Like Australia and Canada, the changeover passed without incident.

“Traffic signs to indicate speed limits in kilometres per hour instead of miles per hour.”
Road Sign Review 2004

“Motorists in Ireland adapt to the introduction of speed limits set in kilometres per hour rather than miles.”
Mind Your Metric Speed 2005

UKMA Newsletter – Volume 3 Issue 1, February 2005

Metric signs ahead – A report by the UK Metric Association by Robin Paice, 2006 (Ireland, page 55) – ISBN 978-0-9552351-0-8