Background: While rising cancer care costs have been well-documented, the extent to which these costs have translated into increased patient financial burden is unclear. To address this question, we used a nationally, representative panel survey to characterize trends over time in the out-of-pocket (OOP) costs of newly diagnosed cancer patients. Methods: Medicare-eligible, community-dwelling participants in the biennial Health and Retirement Study who reported a new cancer diagnosis between 2002-2012 were identified (N = 1409). Respondent-reported OOP costs included the following categories: hospital stays, doctor visits, outpatient surgery, prescription drugs, home health, dental care, and special facilities. A multivariate generalized linear model and quantile regression were used to assess the mean, median, and 90^thpercentile of OOP costs. Adjusted levels of OOP costs were compared over time using a contrast test. Results: Mean annual OOP costs decreased from $7868 (95% CI: $6477 - $9259) for patients with a new cancer diagnosis at the 2002 survey to $4242 (95% CI: $2642 - $5841) for patients with a new cancer diagnosis at the 2012 survey, a decline of $3626 (95% CI: $1508 - $5745, p = 0.001). Median annual OOP costs declined by $580 (95% CI: $66 - $1095, p = 0.03). The steepest decline in OOP costs occurred between 2004 and 2008 (mean: $5070, 95% CI: $2944 - $7195, p < 0.001; median: $1031, 95% CI: $515 - $1547, p < 0.001), while OOP costs did not significantly change between 2008 and 2012 (mean: $779, 95% CI: -1411 – 2969, p = 0.486; median: $17, 95% CI: -515 – 549, p = 0.949). The 90^th percentile of annual OOP costs similarly declined over the study period from $13,203 (95% CI: $11,403 - $15,002) to $8063 (95% CI: $5,995 - $10,131), a decline of $5,140 (95% CI: $2,340 - $7,880, p < 0.001). Conclusions: Despite the growing costs of cancer care,Medicare patients with newly diagnosed cancer were increasingly shielded from high OOP costs over the study period, with a sharp decline between 2004 and 2008 which may be attributable to the introduction of Medicare part D. Given the more recent plateau in OOP costs and proposals to increase cost-sharing in this population, close monitoring of OOP cost trends will be important for avoiding excessive financial burden.