The capital Brussels, the note also highlights, is expected to see the sharpest impact.
"We might see a hit on airlines, rail services and other travel related industries, a major risk given tourism contributed over 5.0 percent to Belgian GDP (gross domestic product) in 2015," Peck wrote.
A number of local amenities will likely be closed in the coming days, which could be particularly disruptive for restaurants, bars and cafes that are usually busy ahead of the Easter bank holiday weekend which runs from March 25 to 28, the note explained.
But the effects may take time to surface, appearing only in second-quarter growth figures which IHS now expects could be pushed down from current projections of 0.4 percent to 0.3 percent, eventually knocking full-year GDP for 2016.
"The timing of the event at the end of the first quarter implies a negative visible impact on the growth forecast for 2016 as whole, which will be lowered from 1.6 percent to 1.45 percent in the next update." The Belgian economy grew 1.3 percent in both 2014 and 2015, according to the European Commission.
However, "as terrible as the events in Brussels have been, economic activity is typically pretty resilient to terrorist attacks," Peck wrote, noting relatively strong economic data following the 2005 London bombings, the Madrid attacks in 2004 and the most recent terror attacks in Paris last November.