Sofia airport is only an hour away from Borovets and is where we recommend that you fly to.
Due to the increase in the number of budget airlines and the fact that prices can change without notice, we feel the best way for you to get the cheapest deal is to simply book it yourselves. To get the cheapest prices, use the planner opposite.
If you prefer to deal with the airlines directly, then the main ones that fly to Sofia are EasyJet (Gatwick or Manchester), Wizz Air, Balkan Air, Alitalia, Lufthansa, Germanwings, and even BA can have some good deals if you book at the right time. Recently Aer Lingus have added Sofia to their routes so you can also fly direct from Dublin.
Prices vary depending on who you fly with and from where, but you should be looking at a return fare of between £50-£100.