Temperature dependent rate coefficients for the reaction of ethyl tiglate (ET) with Cl atoms, were investigated using relative rate method. The rate coefficients were calculated using Canonical Variational Transition State Theory incorporated with Small Curvature Tunneling (CVT/SCT) coupled with interpolated single point energies (ISPE) method over the temperature range of 200–400 K. The thermochemistry, branching ratios for each reaction channels, atmospheric effects and cumulative lifetime of ET were also calculated and discussed. The possible degradation mechanism for the title reactions were also explored.