No Border Checkpoints
One of the most common questions visitors ask when hiring a car in Northern Ireland is whether they can drive into the Republic of Ireland. The answer is a straightforward yes. Since the Good Friday Agreement and the common travel area arrangement between the UK and Ireland, there are no border checkpoints, barriers or passport controls between Northern Ireland and the Republic. You will cross the border without even realising it in most places. The only clues are usually a change in road surface, a switch in the colour of road markings and the appearance of speed limit signs in kilometres per hour rather than miles per hour.
Currency: Sterling to Euro
Northern Ireland uses British pounds sterling while the Republic of Ireland uses the euro. This is probably the most noticeable practical change when you cross the border. Most shops and petrol stations in border towns will accept both currencies, but you will generally get a better rate by using the local currency. Make sure you have some euros in cash or a card that does not charge foreign transaction fees before heading south. ATMs are widely available on both sides of the border. Fuel prices can vary significantly between north and south depending on exchange rates, so it sometimes pays to fill up on whichever side is cheaper at the time.
Speed Limits: Miles to Kilometres
In Northern Ireland, as in the rest of the UK, speed limits are posted in miles per hour. The standard limits are 30 mph in built-up areas, 60 mph on single carriageways and 70 mph on dual carriageways and motorways. The moment you cross into the Republic, everything switches to kilometres per hour. The equivalent limits are 50 km/h in towns, 80 km/h on regional roads, 100 km/h on national roads and 120 km/h on motorways. Your car's speedometer will almost certainly show both units, so keep an eye on the correct scale. It is easy to accidentally drive too fast if you read the mph figure on a km/h road, so stay alert for the first few miles after crossing.
Insurance and Hire Car Cover
Most car hire companies operating in Northern Ireland include Republic of Ireland cover as standard in their rental agreements, since cross-border travel is so common. However, it is always worth confirming this at the time of booking. Check that your collision damage waiver, theft protection and third-party liability all apply south of the border. If you are hiring from a company based in the Republic and driving north, the same advice applies in reverse. Green card insurance is not required for travel between the UK and Ireland, but carrying your insurance documents in the car is always sensible.
Toll Roads in the Republic
The Republic of Ireland has a number of toll roads, including sections of the M1, M3, M4, M7, M8 and the M50 Dublin ring motorway. Most toll plazas accept cash or card payment at the barrier. The notable exception is the M50 eFlow barrier-free toll around Dublin. There is no toll booth on the M50. Instead, cameras read your number plate and you must pay online at eflow.ie before 8 pm the following day. Failure to pay results in a fine. If you are driving a hire car through Dublin, make sure you understand the M50 toll system before you go. Some rental companies will handle the eFlow charge for you and add it to your bill, but check in advance to avoid surprises.
Fuel Prices and Filling Up
Fuel prices differ between Northern Ireland and the Republic, and which side is cheaper changes over time depending on government duties and exchange rates. As a general rule, it is worth comparing prices at stations near the border. In the Republic, fuel is priced in euro per litre. In Northern Ireland it is priced in pence per litre. Keep in mind that diesel is often cheaper than petrol in both jurisdictions, and that rural filling stations sometimes offer lower prices than those on motorways. Many hire cars now come with a full tank, and you are expected to return the car full, so plan your last fill-up accordingly.
Driving on the Left in Both Countries
Both Northern Ireland and the Republic of Ireland drive on the left-hand side of the road. If you are visiting from continental Europe or North America, this is the main adjustment you will need to make, but at least it is consistent on both sides of the border. Roundabouts flow clockwise, overtaking is done on the right, and the driver sits on the right side of the car. Hire cars from local companies will all be right-hand drive. Take extra care at junctions and roundabouts until the left-hand driving feels natural, and be particularly careful when pulling out of car parks and petrol stations.
Practical Tips for Cross-Border Driving
- Documents: Carry your driving licence, hire agreement and insurance documents. A passport or ID is not required at the border but is needed for identification purposes.
- Phone roaming: Check your mobile plan. UK SIMs may incur roaming charges in the Republic and vice versa.
- Road signs: Signs in the Republic are bilingual in English and Irish. Distances are in kilometres.
- Emergency number: 999 works in both Northern Ireland and the Republic. 112 also works across both jurisdictions.
- Sat nav: Set your GPS to kilometres when in the Republic and miles when in Northern Ireland for accurate arrival times.
- Popular cross-border routes: Belfast to Dublin (M1, about 2 hours), Belfast to Donegal (A5/N14, about 2.5 hours), Derry to Galway (N15/N17, about 4 hours).