1,112,020 residents live across 75 ZIPs covering 393 sq mi, served by 24 distinct USPS-recognized cities.
Population moved from 1,085,856 to 1,112,020 from 2014 to 2024 — a +2.4% change. 25 ZIPs gained residents, 16 lost (and 1 held flat).
The county's wealthiest ZIP 22101 (Mc Lean, $250,001 median) and poorest ZIP 22041 (Falls Church, $92,636) are 6.1 miles apart — a 2.7× income gap across local geography.
Median home values vary 3.2× across this county — from $452,300 in 22041 (Falls Church) to $1,449,900 in 22101 (Mc Lean).
Density varies 15× across the county — from 643 people/sq mi in 20124 (Clifton) to 9,462 in 22041 (Falls Church).
Educational attainment ranges from 41.8% bachelor's+ in 22306 (Alexandria) to 85.5% in 22066 (Great Falls) — the breadth of educational profiles across the area.
Within Virginia, this is the #1 most populous of 134 counties and ranks #4 for median household income .
On the national stage, Fairfax County is the #43 most populous US county , ranks #12 for income .
Hosts 4 single-entity Unique ZIPs: 22185A T & T ; 22037Mobil Oil Corp ; 22161Dept Of Commerce ; and 22160National Right To Work Comm .
Weighted by population, the typical household earns about $157,111 across the county — reflecting what a typical resident sees, not a simple ZIP average.
64.8% of adults age 25+ hold a bachelor's degree or higher (498,266 of 769,009 reporting).
47 Standard delivery, 12 PO Box only, 16 single-entity Unique ZIPs serve this county.
28 ZIPs in this county where more than 60% of adults 25+ hold a bachelor's degree — typically college campuses, research enclaves, or tech corridors.
16 ZIP codes in this county serve a single facility — typically theme parks, universities, large corporations, airports, or government complexes.
| ZIP | City | Type | Population | Median Income | Area (sq mi) | 10-yr Growth |
|---|---|---|---|---|---|---|
| 22003 | Annandale | Standard | 57,755 | $138,794 | 12.7 | -3.5% |
| 20171 | Herndon | Standard | 51,286 | $171,372 | 12.3 | 5.4% |
| 22015 | Burke | Standard | 44,647 | $172,563 | 8.9 | -1.1% |
| 20170 | Herndon | Standard | 43,866 | $159,466 | 8.9 | 2.9% |
| 20120 | Centreville | Standard | 42,896 | $152,563 | 18.2 | 4.0% |
| 22033 | Fairfax | Standard | 39,526 | $143,454 | 7.9 | 2.9% |
| 22031 | Fairfax | Standard | 37,276 | $134,577 | 7.4 | 17.7% |
| 22042 | Falls Church | Standard | 35,483 | $138,255 | 6.2 | 8.5% |
| 22079 | Lorton | Standard | 35,284 | $148,134 | 35.1 | 3.7% |
| 22309 | Alexandria | Standard | 34,316 | $107,376 | 8.6 | 1.7% |
| 22153 | Springfield | Standard | 32,664 | $174,228 | 9.0 | 4.5% |
| 20191 | Reston | Standard | 31,011 | $151,185 | 8.0 | 6.9% |
| 22101 | Mc Lean | Standard | 30,953 | $250,001 | 13.1 | 2.4% |
| 22306 | Alexandria | Standard | 30,602 | $97,132 | 6.9 | -7.9% |
| 22315 | Alexandria | Standard | 30,404 | $159,805 | 6.2 | 9.4% |
| 22032 | Fairfax | Standard | 29,240 | $178,394 | 7.3 | -1.5% |
| 22102 | Mc Lean | Standard | 29,184 | $153,949 | 11.9 | 25.1% |
| 22041 | Falls Church | Standard | 29,183 | $92,636 | 3.1 | 3.9% |
| 22152 | Springfield | Standard | 28,814 | $165,906 | 6.2 | -0.7% |
| 22310 | Alexandria | Standard | 28,136 | $166,061 | 6.7 | -2.6% |
| 22150 | Springfield | Standard | 27,955 | $123,114 | 7.9 | 2.9% |
| 20121 | Centreville | Standard | 27,788 | $129,947 | 9.1 | -7.2% |
| 22182 | Vienna | Standard | 27,783 | $205,108 | 12.5 | 6.2% |
| 22312 | Alexandria | Standard | 26,768 | $109,272 | 5.1 | -14.7% |
| 22180 | Vienna | Standard | 26,568 | $177,111 | 5.9 | 9.0% |
| 22043 | Falls Church | Standard | 25,750 | $145,881 | 4.7 | -2.3% |
| 20151 | Chantilly | Standard | 22,610 | $158,271 | 13.7 | 3.0% |
| 20190 | Reston | Standard | 22,012 | $134,746 | 4.4 | 20.5% |
| 22039 | Fairfax Station | Standard | 19,626 | $250,001 | 24.0 | 4.4% |
| 22124 | Oakton | Standard | 18,091 | $218,380 | 10.4 | -2.4% |
| 22066 | Great Falls | Standard | 17,185 | $250,001 | 26.5 | -8.7% |
| 22151 | Springfield | Standard | 17,017 | $156,015 | 5.2 | -3.6% |
| 22303 | Alexandria | Standard | 16,922 | $103,656 | 2.0 | 22.1% |
| 22181 | Vienna | Standard | 15,760 | $211,911 | 5.5 | 4.0% |
| 20124 | Clifton | Standard | 14,375 | $221,060 | 22.4 | -8.5% |
| 22308 | Alexandria | Standard | 14,090 | $212,545 | 4.7 | 6.3% |
| 22044 | Falls Church | Standard | 13,996 | $101,034 | 2.2 | 1.5% |
| 20194 | Reston | Standard | 12,275 | $170,988 | 3.1 | -7.8% |
| 22060 | Fort Belvoir | Standard | 10,641 | $105,605 | 13.7 | 6.4% |
| 22307 | Alexandria | Standard | 10,343 | $141,667 | 4.2 | -0.9% |
| 22027 | Dunn Loring | Standard | 1,939 | $250,001 | 0.7 | -17.1% |
| 22035 | Fairfax | Standard | 0 | — | 0.2 | — |
| 22037 | Fairfax | Unique | — | — | 0.0 | — |
| 20122 | Centreville | PO Box | — | — | 0.0 | — |
| 22034 | Fairfax | Standard | — | — | 0.0 | — |
| 22036 | Fairfax | Standard | — | — | 0.0 | — |
| 22161 | Springfield | Unique | — | — | 0.0 | — |
| 22160 | Springfield | Unique | — | — | 0.0 | — |
| 22158 | Springfield | Unique | — | — | 0.0 | — |
| 22156 | Springfield | Unique | — | — | 0.0 | — |
| 22009 | Burke | PO Box | — | — | 0.0 | — |
| 22159 | Springfield | Standard | — | — | 0.0 | — |
| 22199 | Lorton | PO Box | — | — | 0.0 | — |
| 22121 | Mount Vernon | PO Box | — | — | 0.0 | — |
| 22122 | Newington | PO Box | — | — | 0.0 | — |
| 22183 | Vienna | PO Box | — | — | 0.0 | — |
| 22109 | Mc Lean | Unique | — | — | 0.0 | — |
| 22103 | West Mclean | PO Box | — | — | 0.0 | — |
| 20153 | Chantilly | PO Box | — | — | 0.0 | — |
| 22118 | Merrifield | Unique | — | — | 0.0 | — |
| 22119 | Merrifield | Unique | — | — | 0.0 | — |
| 22082 | Merrifield | Unique | — | — | 0.0 | — |
| 22081 | Merrifield | Standard | — | — | 0.0 | — |
| 22116 | Merrifield | PO Box | — | — | 0.0 | — |
| 22185 | Vienna | Unique | — | — | 0.1 | — |
| 20172 | Herndon | PO Box | — | — | 0.0 | — |
| 22095 | Herndon | Unique | — | — | 0.0 | — |
| 22067 | Greenway | Standard | — | — | 0.0 | — |
| 22106 | Mc Lean | PO Box | — | — | 0.0 | — |
| 22108 | Mc Lean | Unique | — | — | 0.0 | — |
| 22107 | Mc Lean | Unique | — | — | 0.0 | — |
| 20192 | Herndon | Unique | — | — | 0.0 | — |
| 20195 | Reston | PO Box | — | — | 0.0 | — |
| 22096 | Reston | Unique | — | — | 0.0 | — |
| 20196 | Reston | Unique | — | — | 0.0 | — |