Airfares have been increasing for the past year and a half or so, so it’s no longer that easy to find tickets for under EUR 100 (roundtrip within Europe). Brussels Airlines (as well as all other airlines, to tell the truth) has been increasing its prices on an ongoing basis, despite regular promotional sales, which are often not that interesting unless you can fly during the week.
Still, you might want to check out tomorrow’s sale: Thursday, 31 January from 18h00 through midnight, if you’re planning to travel between 17 April and 31 August to any of the “sunny destinations”, i.e., Spain, Italy, southern France, Portugal. (But check also the local national airlines – Iberia, Alitalia (beware delays and cancellations), Air France (usually quite expensive), TAP – because if you’re booking well enough in advance, tickets are often cheaper with those other airlines….)
Another tip: Look at low cost airlines. You can find a list based on departure city, as well as destination on Whichbudget.com
If for some reason you’re considering traveling to Germany or to destinations outside Europe, you might want to take a look at Lufthansa, as it’s currently celebrating its 50th anniversary with some special offers, which allow you to book tickets to Germany, for instance, for less than EUR 100 (all inclusive, roundtrip), which means lower prices and better service than Brussels Airlines.
And don’t forget to enroll in Frequent Flyer programs – they’re free and worth the few minutes it takes to sign up… but more about that later…