Does putting a mattress in the sun kill bed bugs effectively?

No, simply putting a mattress in the sun is not an effective way to kill bed bugs. While heat treatment is a proven method for eliminating bed bugs, sunlight alone rarely achieves the necessary temperatures to be effective. Bed bugs and their eggs require sustained exposure to temperatures of at least 45°C (113°F) to be killed. A full-sized mattress, with its insulating materials like foam and springs, typically doesn’t heat evenly or deeply enough in direct sunlight to reach this threshold. For small items like pillows or luggage, sunlight can be effective if combined with clear, sealed plastic bags to trap and amplify the heat. However, for mattresses, this method is impractical unless you meticulously encase sections in heat-treatment bags and monitor internal temperatures with a thermometer. Even then, it’s often insufficient for thorough eradication. To effectively combat a bed bug infestation, combine sunlight treatments (when applicable) with other proven methods like vacuuming, mattress encasements, washing bedding at high temperatures, and seeking professional pest control services. Heat treatments using specialized equipment remain the most reliable approach for complete elimination.