When saving for retirement, it is important to be well diversified from tax perspective because once in retirement, drawing from various account types to fund spending needs may impact not only the income taxes owed, but how much Social Security may be subject to income taxes and/or Medicare surcharges owed. Currently, qualified withdrawals from Roth and Health Savings accounts are tax-free and are not included in Social Security taxation or Medicare surcharge requirements. As a result, they are a nice compliment to taxable and tax-deferred accounts because they can provide greater flexibility and control during retirement.