This paper is part of the variationist studies made under the internacional project known as PRESEEA (Project for the Sociolinguistic Study of Spanish From Spain and America). This investigation presents and contrasts the mechanisms and mitigating functions of Spanish spoken in three different areas in Spain and one in America: Las Palmas de Gran Canaria, Madrid and Valencia, and Santiago de Chile. In addition to diatopic contrast, diastratic variation is also studied according to educational levels, age groups and speakers' gender. Following the methodology proposed by Ana M. Cestero and Marta Albelda for the sociopragmatic study of mitigation, an analysis of the phenomenon is carried out which includes four types of factors: linguistic, pragmatic, enunciative and socio-situational. A corpus of 72 semi-directed interviews with a total duration of 36 hours is analysed. We start from a rhetorical-communicative definition of mitigation, as a pragmatic category intended to decrease the intensity of what is being expressed and to reduce the epistemic commitment of the speakers to what is being said. The results of the analysis performed show different patterns of sociolinguistic and dialectal behaviour in relation to the strategys of mitigation in the worked areas. Relevant differences are observed both in the use itself of mitigation in interaction as well as in the use of the 25 mechanisms of mitigation studied and in the three main functions established: self-protection, prevention and repair.