The IRS has said (https://www.irs.gov/tax-professionals/aca-information-center-for-tax-professionals) that it will not accept electronically filed returns for processing during the 2018 filing season (2017 returns) if the taxpayer fails to comply with the individual mandate. This means doing any of the following:
The IRS did not do this for 2016 returns. However, as it reviews 2016 returns that have been filed, it may send letters to taxpayers who did not indicate they had coverage, were exempt, or paid the penalty.
Shifting income to a later year, such as where you defer taxable interest to the following year by purchasing a T-bill or savings certificate maturing after the end of the current year. Investments in qualified retirement plans provide tax deferral.