In 2019, 21,148 people moved to King County from within the state, according to migration data from the Internal Revenue Service.
This is an increase over the year before, when 20,998 people migrated to King County from elsewhere in the state.
The number of people moving to King County is offset by the 70,191 residents who left the area during the same year.
There were 60,749 people who left the year before.
Migration data for the U.S. is based on year-to-year address changes reported on individual income tax returns filed with the IRS.
According to the U.S. Census Bureau, most U.S. regions saw their numbers shrink.
The Northeast region of the U.S. suffered the greatest losses, while the Midwest saw population growth.
The U.S. Census Bureau found migration within the country mainly flows to the South, with many people moving to areas of Florida and Texas.
| Years | Inflow | Outflow | Domestic Migration |
|---|---|---|---|
| 2017-2018 | 21,084 | 64,891 | -43,807 |
| 2018-2019 | 20,998 | 60,749 | -39,751 |
| 2019-2020 | 21,148 | 70,191 | -49,043 |
