Last week, the Internal Revenue Service (IRS) published updated migration data based on income tax returns, showing where taxpayers are moving to and from at the county level. We’ve compiled the data, shown in the interactive below, and have highlighted the areas experiencing the highest population gains from migration.
Numbers of exemptions claimed on tax returns are commonly used to approximate population totals. Using this metric, only about 15 million Americans relocated to a new county between 2013 and 2014. For most counties, net migration gains or losses are fairly small -- typically less than 1,000 tax returns -- in a given year.
Several of the nation’s largest counties do, though, experience significant shifts from year to year. As one would expect, it’s the larger counties in the Sun Belt that generally register the highest migration gains. The following counties saw the top 10 migration increases, as measured by net changes of numbers of exemptions, between 2013 and 2014:
1) Travis County, Texas, had nearly 123,802 new residents move in -- by far the most of any county nationally. To put that in perspective, it’s more than three times the tally of the next highest county. The region, home to Austin, has seen significant population and economic growth in recent years. Data suggests people are moving from long distances into the area (those migrating from out of state account for nearly all of the net increase).
2) Jefferson County, Colo., gained 34,205 new residents (compared to less than 4,000 over the previous two years), with nearly all movers coming from neighboring Broomfield County. We've reached out to the county for an explanation and will update when we hear back. (It's possible that the IRS data contains an error.)
3) Maricopa, County, Ariz., recorded a net migration increase of 17,827. The county, which includes Phoenix and its surrounding suburbs, has long benefited from retirees moving in.
4) Fort Bend County, Texas, welcomed a net total of 17,462 residents -- a figure that’s increased over the previous two years. Unlike Travis and Maricopa counties, migration coming from within the state accounted for the majority of its increase.
5) Clark County, Nevada, recorded a net gain of 14,292 residents for the year. The vast majority of its new residents migrated from out of state, particularly from neighboring California. The county has also seen net migration jump quite a bit in recent years, up from 8,613 for 2011-2012.
6) Collin County, Texas, which comprises the northern part of the Dallas-Fort Worth-Arlington metro area, added a net total of 13,428 residents. The county’s newcomers also tend to be relatively wealthy, with their adjusted gross incomes averaging $73,930 per tax return.
7) Denton County, Texas, which borders Collin County, experienced a similar net gain of 12,461 residents. Migration from within Texas and outside the state accounted for roughly equal portions of the county’s net migration gain.
8) Montgomery County, Texas, saw a net increase 11,652 for the year, with about half of its new residents moving from neighboring Harris County. Households migrating into the county reported average gross incomes of $82,316.
9) Palm Beach County, Fla., is known as a top destination for wealthy retirees, a fact reflected in the county’s migration data. Many of its new residents, who made up a net gain of 11,303, moved in from other parts of Florida or the New York Metro area. Gross incomes for new Palm Beach County residents averaged $95,030 per tax return, one of the highest amounts nationally.
10) Lee County, Fla., another hot area for retirees, welcomed a net total of 10,609 residents. Its new households also tend to be wealthy, (but not quite as wealthy as Palm Beach County) with incomes averaging $82,884.
Counties recording the largest net migration losses were Los Angeles County, Calif., (-53,670); Cook County, Ill., (-49,142); Manhattan, N.Y., (-28,123); and Brooklyn, N.Y., (-27,416). Population losses for these counties are largely offset by international migration, most of which is not reflected in the IRS data.
Select your county and a time period to view its most recent IRS migration data:
County migration data tool page
IRS methodology
