I only had health coverage for part of 2019, but I was covered the entire time I was a resident of DC. Do I still need to say "I didn't have health insurance all year"?

On a federal tax return there is no longer a question concerning your health care coverage.  The individual mandate penalty for not having insurance was removed from the tax code after tax year 2018.

 

If you received a Form 1095-A for health insurance through one of the State Marketplace Exchanges then you need to enter the form on your tax return.

 

To enter your Form 1095-A -

• Click on Federal Taxes (Personal using Home and Business)
• Click on Deductions and Credits
• Click on I'll choose what I work on (if shown)
• Scroll down to Medical
• On Affordable Care Act (Form 1095-A), click the start or update button

Or enter 1095-a in the Search box located in the upper right of the program screen. Click on Jump to 1095-a

This is for District of Columbia taxes.

 

On that screen, you would say that you didn't have coverage the whole year.  And then after that say you had coverage for part of the year on the next question.  Then indicate the months you had coverage.  Next you would say you have a coverage exemption for being uninsured, then use the exemption code "I - Nonresident of the District" for the months you were not a resident of DC, including the month that you moved into DC.