We investigated the potential of carbon dioxide (CO₂) fumigation as a method for controlling bed bugs, Cimex lectularius L. The effect of bed bug developmental stage, temperature, and CO₂ concentration on the minimum time to kill 100% of bed bugs was determined. The minimum CO₂ concentration lethal to all bed bug stages was ≈30% with 24 h exposure time at 25°C. The minimum fumigation time required to kill 100% of eggs using 100% CO₂ at 20, 25, and 30°C were 3, 7, and 8 h, respectively; the minimum fumigation time to kill 100% of adult males/nymphs were 8,13, and 14 h, respectively. The minimum time to kill 100% of adult males/nymphs using 50 and 70% CO₂ at 25°C were 18 and 16 h, respectively. We found that eggs were not completely killed after 24 h fumigation when the CO₂ concentration was lower than 80%. Thus, bed bug eggs were more susceptible to 100% CO₂ fumigation than nymphs and adult males but more tolerant than nymphs and adult males with lower CO₂ concentration (50–80%). There were no significant differences among nymphs, adult males, and adult females in their susceptibility to 100% CO₂ fumigation. A 24 h fumigation in sealed 158 liter (42 gallon) heavy duty garbage bags filled 90% full with fabric materials and/or boxes and 1,350 g dry ice per bag was sufficient to kill all stages of bed bugs hidden in the materials at room temperature (23–24°C). Sealed heavy duty garbage bags maintained ≥94% CO₂ for at least 24 h. Custom-made double zipper plastic bags (122 × 183 cm) were also used to evaluate the effectiveness of CO₂ fumigation for controlling bed bugs. Each bag was filled with fabric and boxes to 50–90% full. Bed bugs were hidden in various locations of each bag. CO₂ was introduced into the bags through a CO₂ cylinder. CO₂ fumigation lasting 24–48 h was sufficient to kill all stages of bed bugs at room temperature, depending on the quantity of materials placed in each bag and whether CO₂ was introduced one or two times at the onset. CO₂ is an effective alternative to conventional fumigants for eliminating bed bugs hiding in infested household items such as clothing, shoes, books, electronics, sofas, and so forth.