A discount airline based in Iceland offering rock-bottom prices for flights between Canada and Europe says it has been so overwhelmed with demand from Canadians that it is moving up its launch date and offering more flights than originally planned.

WOW Air made headlines last October with plans to offer one-way flights from Toronto and Montreal to Iceland starting at $99, with all airport charges and taxes included. Flights to Europe were advertised as low as $149 one-way, depending on the destination and the time of year.

Originally the airline said four flights a week would be offered out of Montreal's Pierre Elliott Trudeau airport as of May 12, 2016, and out of Toronto's Lester B. Pearson airport as of May 20, 2016, with all flights going to Europe via Iceland's capital, Reykjavik.

But on Monday, the airline says it is moving up those launch dates, to May 4 from Montreal, and to May 11 for Toronto flights.

And the airline is adding more flights a week, too: six a week from Toronto and five a week from Montreal, an increase on the original plan of four flights a week each.

"Due to great demand since we first announced our Canadian routes in October 2015, we are increasing capacity for both the Montreal and Toronto routes," CEO Skúli Mogensen said in release. "We are thrilled with the response to our super low fares, and we will continue adding even more interesting destinations across Europe that will connect with Canada at great prices."

Growing market

All flights will use Airbus A320 or A321 long-range aircraft.

By the summer, WOW says it plans to offer more destinations across North America and Europe, up to 27 destinations including London, Paris, Berlin, Copenhagen, Los Angeles, San Francisco, Washington DC, Boston, Montreal and Toronto.

The airline, founded in 2011, posted its first annual profit ever last year, and expects to double ticket sales in 2016 as it expands.

While WOW's main appeal is rock-bottom prices, the airline does charge extra fees for everything from extra leg room and baggage to flight changes.

WOW isn't the only airline hoping to move in on what they deem to be a growing market for discount travel. In January, Canadian airline NewLeaf announced plans to fly between seven underserved Canadian markets as of February 2016.

So far that hasn't happened as NewLeaf then ran into regulatory turbulence and suspended sales until it could sort out its issues, but the company still says it plans to launch in the spring.