A personnel carrier and reconnaissance vehicle based on the same chassis was designated as Laffly S15R. It had a different, lighter rear cab and a different transmission that allowed for higher road speed.
The Laffly S15TOE (théâtre d'opérations extérieures: "overseas theatre of operations") was a scout car designed and built for service in French African colonies. The S15 chassis was preserved, but an armoured cabin protected the engine and crew, with a small turret that was armed with one single Reibel machine gun.
When France delivered 41 Renault R-35 tanks to Romania in 1939, a number of Laffly S15T artillery tractors were also delivered. These gun tractors were used by the 2nd Armoured Regiment's support services.