Irmo: Demographics & People
Irmo's population stands at 11,813 people, in 4,632 households. Population grew 0.1% from 11,799 (2022) to 11,813 (2024). Median age 40.3 years. (5.9y older than Richland County; 3.4y older than South Carolina). Children under 18 are 23% of the population. Population is 58% White (non-Hispanic) and 27% Black. The community is moderately diverse (Simpson index 0.50). 71% of households are family-led. County is gaining 10,414 residents per year (2022-2023). County health: 39% adult obesity, 14% smoke.
- 2.6 people per household (vs South Carolina avg 2.5).
- 29% non-family households (singles, roommates) (vs South Carolina 38%).
- 62 dependents per 100 working-age (youth + seniors / 18-64) (vs South Carolina 68).
Population & Trend
Population grew 0.1% from 11,799 (2022) to 11,813 (2024) — close to the U.S. annual rate of ~0.6%/yr. Estimated 2026 population: ~11,827 (extrapolated at 0.1%/yr trend).
| Census data vintage | 2024 |
|---|---|
| Population | 293,991 people |
| Annual growth rate · Population change | 0.1% |
| Annual growth rate · Population (2022) | 11,799 |
| Annual growth rate · Population (2024) | 11,813 |
| Annual growth rate · Population growing | Yes |
| Annual growth rate · Trend category | stable |
| Population | 11,813 people (vs South Carolina 24,505) |
| Population Estimate | 11,846 |
Sources: Census ACS 5-Year 2023, Table B01003 · Refreshed 2026-04-12
Age Distribution
Median age 40.3y is 1.4 years older than the U.S. median (38.9y). Children under 18 make up 23% — near the U.S. share of ~22%.
| Age Summary · Median age | 40.3 years (vs South Carolina 36.9y) |
|---|---|
| Age Summary · Children Pct | 22.9% |
| Age Summary · Character | established |
| Age Summary · Total Pop | 11,813 |
| Age Summary · Under 18 | 2,701 |
| Age Summary · 18 To 34 | 2,477.0× |
| Age Summary · 35 To 64 | 4,801.0× |
| Age Summary · 65 Plus | 1,834 |
| Population under 18 | 2,701 |
| Median age | 40.3 years (vs South Carolina 36.9y) |
Sources: Census ACS 5-Year 2024 — place-level B01001 query · Census ACS 5-Year 2023 · Refreshed 2026-04-29
Race, Ethnicity & Diversity
Of 11,813 residents, race / ethnicity breaks down by Census ACS counts (a person can identify with one or more groups). The Simpson diversity index is 0.50 (0 = single group, 1 = perfectly even distribution); this is read as moderately diverse.
| White residents | 7,233 |
|---|---|
| Black residents | 3,508 |
| Asian residents | 292 |
| Hispanic or Latino residents | 331 |
| Diversity Index · Diversity index (Simpson) | 49.8% |
| Diversity Index · Diversity label | moderately diverse |
| Diversity Index · Groups counted | 4 |
| Diversity Index · Largest group share | 63.6% |
| Asian population | 4.3% (vs South Carolina 1.8%) |
| Black population | 27.4% (vs South Carolina 21.3%) |
| Hispanic or Latino population | 5.6% (vs South Carolina 6.6%) |
| White (non-Hispanic) population | 58.1% (vs South Carolina 60.8%) |
Sources: Census ACS 5-Year 2023 · Refreshed 2026-04-12
Ancestry
Self-reported ancestry from Census ACS — what residents report as their ethnic origin, separate from race. Counts can exceed population because people can list multiple ancestries.
Top (8)
Citizenship & Origin
Where residents were born and their citizenship status (Census ACS). 1.5% are foreign-born — below the U.S. average of 13.9%. 6% have naturalized to U.S. citizenship.
| Residents born in this state | 7,030 |
|---|---|
| Residents born in another state | 3,930 |
| Share born in this state | 59.5% |
| Share born in another state | 40.5% |
| Native-born U.S. citizens | 33.3% |
| Foreign-born residents | 1.5% |
| Naturalized citizens | 5.7% |
| Total foreign-born residents | 565 |
| From Europe | 126 |
| From Africa | 329 |
| Census Foreign Born · Caribbean | 90 |
Households & Family Composition
4,632 households. Averaging 2.5 people each — matches the U.S. average of 2.5. 71% are family households — above the U.S. share of ~65%. Of 3,345 families, 23% are married couples with children.
| Children under 18 | 2,540 |
|---|---|
| Total families | 3,345 |
| Married couples with children | 758 |
| Single-parent households | 77 |
| Average household size | 2.48 |
| Women who gave birth (past year) | 14.7% |
| Grandparents living with grandchildren | 278 |
| Grandparents responsible for grandchildren | 20 |
| Family households | 3,292 households (vs South Carolina 5,968) |
| Households that are families | 71.1% (vs South Carolina 61.8%) |
| Total households | 4,632 households (vs South Carolina 9,745) |
Sources: Census ACS 5-Year 2023 · Refreshed 2026-04-12
Residential Stability & Migration
How long residents have lived here and where they came from. 18.0% moved within the county in the past year — the U.S. baseline is roughly 8–10%. The surrounding county is gaining 10,414 residents per year on net (IRS migration data).
| Moved within the county (past year) | 18.0% |
|---|---|
| Migration · People moving in (annual) | 293,213 |
| Migration · People moving out (annual) | 282,799 |
| Migration · Net migration (in − out) | 10,414 |
| Migration · Population growing | Yes |
| Migration · Year | 2022-2023 |
Sources: IRS SOI Migration 2021-2022 · Refreshed 2026-04-12
Disability
Census ACS measures self-reported functional limitations — vision, hearing, mobility, cognitive, self-care, or independent-living. The U.S. baseline disability rate is about 12–13%; rates trend higher with median age.
| Residents with a disability | 997 |
|---|---|
| Disability rate | 8.6% |
Group Quarters
Group quarters are non-household living arrangements counted by the Census — college dormitories, nursing homes, military barracks, group homes, correctional facilities, and similar institutional or shared housing. 43 residents live in group quarters (0.4% of population).
| Living in group quarters | 43 |
|---|
Other
| Congressional District · District | 2 |
|---|---|
| Congressional District · Congress | 118th |
| Cdc Birth Rate · Fips | 45063 |
| Cdc Birth Rate · State Fips | 45 |
| Cdc Birth Rate · County Fips | 063 |
| Cdc Birth Rate · County | Lexington |
| Cdc Birth Rate · Birth Rate | 19.3% |
| Cdc Birth Rate · Lower Ci | 17.80 |
| Cdc Birth Rate · Upper Ci | 20.80 |
| Cdc Mortality · Fips | 45063 |
| Cdc Mortality · County | Lexington County |
| Cdc Mortality · Urban Rural | Medium metro |
| Cdc Mortality · Total Deaths 2020 2023 | 11,824 |
| Cdc Vaccination · Fips | 45063 |
| Cdc Vaccination · County | Lexington County |
| Cdc Vaccination · Dose1 Pop Pct | 67.4% |
| Cdc Vaccination · Series Complete Pct | 58.2% |
| Cdc Vaccination · Booster Pct | 46.3% |
| Cdc Vaccination · Population 2019 | 298,750 |
| Cdc Vaccination · Metro Status | Metro |
| Family Score · Score | 9.50 |
| Family Score · Schools | 9 |
| Family Score · Childcare Centers | 5 |
| Family Score · Youth Sports Orgs | 5 |
| Family Score · Children Pct | 22.9% |
| Family Score · Rating | excellent |
| Town Summary · Key Facts | population 11,813, stable, established, upper-middle, white collar |
| Town Summary · Population | 11,813 people (vs South Carolina 24,505) |
| Town Summary · County | Lexington County |
Sources: NCES school congressional district assignment · federal dataset cascade