How bad is Sofia air quality in winter, really? I have mild asthma

Honest answer: winter air pollution in Sofia is a real issue, but the headlines flatten a more nuanced picture. The mechanism: Sofia sits in a valley ringed by mountains, and on cold, windless winter nights a temperature inversion traps emissions - mainly wood and coal heating from houses on the outskirts and surrounding villages, plus traffic. On those nights, PM2.5 spikes well above EU limits. The key word is nights and episodes: this is not a permanent smog dome. Most winter days are fine, especially after wind or snow, and from roughly April to October air quality is genuinely good. In practice you might see a handful of bad episodes per winter month, each lasting one to a few days. What residents with respiratory sensitivities actually do: check live data - the AirBG citizen sensor network and apps like IQAir show real-time readings per neighborhood - and shift outdoor exercise to clean days. Run a HEPA air purifier in the bedroom; they are cheap and effective and most expats here own one. Choose your neighborhood with altitude in mind: districts higher up the Vitosha slope such as Boyana, Dragalevtsi and upper Lozenets sit above the worst inversion layer and consistently measure cleaner than the low-lying northern and eastern districts. With well-controlled mild asthma, an inhaler plan, a purifier, and a sensible neighborhood choice, most people in your position live here without drama - I would not cancel the move over it, but do discuss it with your doctor and visit in January before signing a long lease. Neighborhood breakdowns are in our guide at /guides/living-in-sofia-guide.