Rate coefficients have been measured for the gas phase reactions of hydroxyl (OH) radicals with three acetals, di-n-propoxymethane (n-C₃H₇OCH₂On-C₃H₇), di-n-butoxymethane (n-C₄H₉OCH₂On-C₄H₉) and 1,3-dioxolane. The experiments were carried out using the pulsed laser photolysis - laser induced fluorescence technique over the temperature range 243–372 K and the kinetic data were used to derive the following Arrhenius expressions (in units of cm³ molecule⁻¹ s⁻¹): di-n-propoxymethane, k₁=(4.39±1.06)×10⁻¹² exp[(563±74)/T]; di-n-butoxymethane, k₂=(5.15±0.66)×10⁻¹² exp[(590±38)/T]; and 1,3-dioxolane, k₃=(6.70±0.86)×10⁻¹² exp[(154±36)/T]. At 298 K, the rate coefficients obtained (in units of 10⁻¹² cm³ molecule⁻¹ s⁻¹) are: k₁=(27.6±2.3), k₂=(37.0±5.2) and k₃=(11.1±0.9). The results are discussed in terms of structure–activity relationships and used to derive atmospheric lifetimes for these acetals.