While many studies have examined the sources of stress that sports officials encounter, this study represents an exploration into the influence that certification level has on the sources and intensity of ice hockey officials’ experiences of stressful events.Participants were 421 officials from six certification levels of Canadian ice hockey. The 15-item Hockey Officials Sources of Stress Inventory (HOSSI) was developed and content validated for this study.Overall, the intensity of the stressors identified was moderate. The three events consistently among the top five rated stressors across certification level were making a controversial call, difficulty working with a partner official, and confrontation with coaches. Further examination of the subscales of verbal and physical abuse and fear of mistakes by means of a MANCOVA (using age and officiating experience as covariates) showed significant differences to exist among certification level for each subscale, F(10,786)=5.175, p<0.0001 and F(10,786)=7.546, p<0.0001, respectively.Results indicate that officials in the lowest level of the officiating ranks (level 1) experience less stress than the other levels of officiating. Also, levels 1 and 6 officials experience more stress from fear of mistakes than from abusive events. These findings suggest that intervention programs need to be cognisant of the differences in the stressful experiences based upon certification levels.