Background: The six minute walk test (6MWT) is an important physical performance measure used in older people. Aim: To assess the total distance walked and the physiological cost of the 6MWT in non-disabled older people. Material and Methods: Fifty six females aged 69 ± 5 years with a body mass index (BMI) of 31 ± 4 kg/m2 and sixteen males aged 70 ± 7 years with a BIM of 29 ± 4 kg/m2 underwent a 6MWT. The total distance walked was registered and the physiological cost (PC) of the test was calculated as the ratio between the difference of heart rate at work and at rest and the walking speed. The socioeconomic status (SES) of participants was determined using a questionnaire designed in Chile. Results: Among participants of middle-lower and middle-upper SES, the PC was 0.43 ± 0.1 and 0.44 ± 0.09 beats/min, respectively, p = NS. Males of middle-upper SES had a significantly higher PC than their middle-lower SES counterparts. The total distance walked was 493 ± 58 and 501 ± 63 m among participants of upper and lower SES. The plateau in reserve heart rate appeared earlier among participants of upper SES of both genders. Conclusions: Older participants of middle-upper SES had a higher physiological efficiency during the execution of the 6MWT.