We employ a suite of 75 simulations of galaxies in idealised major mergers ( stellar mass ratio \sim 2.5:1 ) , with a wide range of orbital parameters , to investigate the spatial extent of interaction-induced star formation . Although the total star formation in galaxy encounters is generally elevated relative to isolated galaxies , we find that this elevation is a combination of intense enhancements within the central kpc and moderately suppressed activity at larger galacto-centric radii . The radial dependence of the star formation enhancement is stronger in the less massive galaxy than in the primary , and is also more pronounced in mergers of more closely aligned disc spin orientations . Conversely , these trends are almost entirely independent of the encounter ’ s impact parameter and orbital eccentricity . Our predictions of the radial dependence of triggered star formation , and specifically the suppression of star formation beyond kpc-scales , will be testable with the next generation of integral-field spectroscopic surveys .