Idylwood is a census-designated place (CDP) in Fairfax County, Virginia, United States. The population was 17,954 as of the 2020 census. It is bordered to the east by the city of Falls Church, to the north by Pimmit Hills and Tysons Corner, to the west by Dunn Loring, to the southwest by Merrifield, and to the south by West Falls Church. The Capital Beltway forms the western border of the CDP, Virginia Route 7 (Leesburg Pike) forms the northern border, and U.S. Route 29 (Lee Highway) forms the southern border.
According to the United States Census Bureau, the CDP has a total area of , of which is water.
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Racial and ethnic composition
{| class="wikitable sortable" style="text-align:center;"
|+Idylwood CDP, Virginia – Racial and ethnic composition<br><small></small>
!Race / Ethnicity <small>(NH = Non-Hispanic)</small>
!Pop 2000
!Pop 2010
!style="background-color: #ffffb3;" |Pop 2020
!% 2000
!% 2010
!style="background-color: #ffffb3;" |% 2020
|-
|White alone (NH)
|8,775
|8,632
|style='background: #ffffe6; |7,930
|54.83%
|49.93%
|style='background: #ffffe6; |44.17%
|-
|Black or African American alone (NH)
|1,058
|950
|style='background: #ffffe6; |953
|6.61%
|5.50%
|style='background: #ffffe6; |5.31%
|-
|Native American or Alaska Native alone (NH)
|32
|29
|style='background: #ffffe6; |24
|0.20%
|0.17%
|style='background: #ffffe6; |0.13%
|-
|Asian alone (NH)
|3,067
|3,660
|style='background: #ffffe6; |4,351
|19.16%
|21.17%
|style='background: #ffffe6; |24.23%
|-
|Native Hawaiian or Pacific Islander alone (NH)
|5
|8
|style='background: #ffffe6; |12
|0.03%
|0.05%
|style='background: #ffffe6; |0.07%
|-
|Other race alone (NH)
|44
|79
|style='background: #ffffe6; |125
|0.27%
|0.46%
|style='background: #ffffe6; |0.70%
|-
|Mixed race or Multiracial (NH)
|403
|458
|style='background: #ffffe6; |898
|2.52%
|2.65%
|style='background: #ffffe6; |5.00%
|-
|Hispanic or Latino (any race)
|2,621
|3,472
|style='background: #ffffe6; |3,661
|16.38%
|20.08%
|style='background: #ffffe6; |20.39%
|-
|Total
|16,005
|17,288
|style='background: #ffffe6; |17,954
|100.00%
|100.00%
|style='background: #ffffe6; |100.00%
|}
2020 census
As of the 2020 census, Idylwood had a population of 17,954. The median age was 35.8 years. 23.2% of residents were under the age of 18 and 11.4% of residents were 65 years of age or older. For every 100 females there were 97.8 males, and for every 100 females age 18 and over there were 94.7 males age 18 and over.
100.0% of residents lived in urban areas, while 0.0% lived in rural areas.
There were 6,847 households in Idylwood, of which 35.3% had children under the age of 18 living in them. Of all households, 49.3% were married-couple households, 19.8% were households with a male householder and no spouse or partner present, and 25.4% were households with a female householder and no spouse or partner present. About 25.4% of all households were made up of individuals and 6.8% had someone living alone who was 65 years of age or older.
Education
Fairfax County Public Schools operates public schools serving Idylwood. George C. Marshall High School is in Idylwood.
Parks and recreation
The Fairfax County Park Authority operates the Jefferson District Golf Course in the southwest corner of the CDP. Idylwood Park, in the western part of the CDP north of I-66 and east of the Beltway, is a county park with baseball, softball, and soccer fields, plus basketball and tennis courts.