Prices in Belfast’s branch of hip restaurant chain The Ivy are up to 29% cheaper than those in Dublin, Belfast Telegraph analysis has found.

While The Economist’s Big Mac Index measures currency performance, our new Shepherd’s Pie Index reflects Belfast’s value for money for eating out compared to its southern counterpart.

For example, shepherd’s pie at The Ivy in Dawson Street in Dublin is nearly 30% more expensive at £21.80 for a portion (€25.95), compared to Belfast’s £16.95.

On Monday, we compared the prices of nibbles, starters, mains and two desserts at the restaurant, which opened at Donegall Place last month, with prices in the six-year-old Dublin venue.

On the basis that €1 is worth 84p, price differences between key menu items range from 10% to 29%, with savings of over £5 on cod fillet.

For nibbles to get things started, zucchini fritti is €8.95 (£7.52) in Dublin, but £5.95 in Belfast — 26% cheaper.

You’ll save nearly the same percentage on a crispy duck salad, which is €15.95 (£13.40) in Dublin but £10.75 in Belfast. There’s a narrower saving on a salt and pepper squid tempura, which is just 15% cheaper in Belfast than Dublin, at £10.95.

But the gap is widest on its shepherd’s pie, probably The Ivy’s most famous dish and one many of us gravitate towards in colder temperatures.

The shepherd’s pie gap is closely followed by the blackened cod fillet, costing €29.95 (£25.16) in Dublin, but £19.95 in Belfast – a price gap of 26%. And a vegetarian option of chargrilled halloumi in Belfast sounds extremely reasonable at £15.95, though in Dublin it will set you back €23.95 (£20.12) — again, a differential of 26%. But the gap tends to be narrower for desserts. A chocolate bombe in Dublin is €13.95 (£11.72), but yours for under a tenner in Belfast at £9.95 — that’s 18% cheaper.

The view down Royal Avenue from The Ivy. Its famous shepherd’s pie is 29% cheaper in Belfast than Dublin

The restaurant chain, which no longer has a spokesperson in Northern Ireland, did not respond to a request for comment.

Andrew Webb, chief economist at business advisory firm Grant Thornton, said he was not surprised by the price difference.

“There’s undoubtedly a lot that goes into an Ivy shepherd’s pie,” he said.

“There’s rent, rates, heat, light and power, staff costs, supplier costs, local taxes, plus other local context, such as the amount of competition.”

The restaurant opened to a fanfare in Belfast last month, and is now on the hunt for a new general manager. Its general manager at the time of opening last month was Julian Henry, the former manager of Lisburn Road venue, Shu.

Colin Neill, chief executive of Hospitality Ulster, said the UK Ivy restaurants had some competitive advantages.

He added: “They are part of a big chain so they have huge buying power, but I would say part of what’s happening in Dublin is that it’s more costly to take food into the Republic from Great Britain as a result of Brexit.”

However, one advantage for restaurants in the Republic is a lower of Vat at 13.5%, compared to the 20% payable by all businesses around the UK.

Crowds at the opening of The Ivy in Belfast last month

Mr Neill said that with most restaurants in Northern Ireland independent, they didn’t have the buying power which brought prices down for The Ivy outposts around the UK.

“Lots of the industry is finding it hard to make a profit and wishing they could charge the lower prices the Ivy is charging,” he added.

Restaurant critic Joris Minne said the higher prices at The Ivy in Dublin were a reflection of its reputation as a costly city. “One of the attractions of Belfast is that you can eat out very well and very finely for a fraction of the cost that it might be in Dublin,” he said. “A lot of people will complain about how expensive Belfast is compared to places like Leeds, Glasgow, Manchester and places like that, and that is true when it comes to cocktails, pints and bistro food, but once you get into higher level, it is cheaper up here.”

Mr Minne said its biggest impact might come from occupying a hitherto neglected part of the city, at the old Cleaver House building on the corner of Donegall Place and Donegall Square.

“The very fact that it is occupying that site and regenerating that part of the city centre is to be welcomed, no matter how good or mediocre the food is,” he added.

“People want a little spark, a little class and a little bit of glamour, and that’s certainly what The Ivy is bringing.”