Abstract Effective collision strengths computed by the R -matrix method are presented for the electron-impact excitation of nitrogen-like S X. The total wave function used in the expansion includes the lowest 11 eigenstates of S X which arise from the 2s 2 2 p 3 , 2 s 2 p 4 , 2 p 5 and 2 s 2 2 p 2 3 s configurations. These 11 LS target states correspond to 22 fine-structure levels, giving 231 possible transitions. All the effective collision strengths for these transitions are tabulated in the range log T (K)=4.6 to log T (K)=6.7. The energy level values and oscillator strengths for allowed transitions are also tabulated. The effective collision strengths were calculated by averaging the electron collision strengths over a Maxwellian distribution of velocities. The present effective collision strengths are the only results currently available for these fine-structure transition rates.