While much research has analyzed the access of Mexican immigrants to health benefits while in the US, little is known about how those who return to Mexico fare. We analyze health care access for Mexican elders with a history of migration to the US. Using a nationally representative dataset of Mexican elders, we find a robust negative association between years spent in the US and the probability of being insured. This result reflects that Mexicans who spend time in the US are less likely to meet vesting requirements in the Mexican social security system. Interestingly, this association does not hold for pension benefits since migrants may qualify for and receive US social security upon retirement in Mexico. The discrepancy can be attributed to the lack of portability in Medicare. Our findings suggest that portability of Medicare benefits will improve health insurance coverage and health care access for elderly Mexicans.