If I had a brief gap when I was not covered by health insurance in 2018, will I owe a payment?

Individuals with no coverage | Individual Responsibility Requirement (Individual Mandate)

Possibly — it depends on how long you were without coverage. Individuals are treated as having minimum essential coverage for a calendar month if they have coverage for at least one day during that month. Additionally, as long as the gap in coverage is less than three consecutive months, you may qualify for an exemption and not owe a payment. (26 U.S.C. § 5000A (e)(4)).

Individuals with no coverage
Individuals with coverage
Coverage for small employers
Post enrollment issues