Buffalo: Demographics & People
Census counts 1,092 people in Buffalo, in 398 households. Population shrank 12.2% from 1,244 (2022) to 1,092 (2024). Median age 39.5 years. (1.4y younger than Harper County; 4.3y older than Oklahoma). Children under 18 are 30% of the population. Population is 71% White (non-Hispanic) and 24% Hispanic or Latino. The community is somewhat diverse (Simpson index 0.31). 83% of households are family-led. County health: 43% adult obesity, 16% smoke.
- 2.7 people per household (vs Oklahoma avg 2.6).
- 17% non-family households (singles, roommates) (vs Oklahoma 39%).
- 97 dependents per 100 working-age (youth + seniors / 18-64) (vs Oklahoma 67).
Population & Trend
Population shrank 12.2% from 1,244 (2022) to 1,092 (2024). Estimated 2026 population: ~962 (extrapolated at -6.1%/yr trend). Census Bureau Vintage estimate: 805.
| Census data vintage | 2024 |
|---|---|
| Population | 3,272 people |
| Annual growth rate · Population change | -12.2% |
| Annual growth rate · Population (2022) | 1,244 |
| Annual growth rate · Population (2024) | 1,092 |
| Annual growth rate · Trend category | shrinking |
| Population | 1,092 people (vs Oklahoma 63,420) |
| Population Estimate | 805 |
Sources: Census ACS 5-Year 2023, Table B01003 · Refreshed 2026-04-12
Age Distribution
Median age 39.5y is 0.6 years older than the U.S. median (38.9y). Children under 18 make up 30% — above the U.S. share of ~22%.
| Age Summary · Median age | 39.5 years (vs Oklahoma 35.2y) |
|---|---|
| Age Summary · Children Pct | 29.5% |
| Age Summary · Character | family-oriented |
| Age Summary · Total Pop | 1,092 |
| Age Summary · Under 18 | 322 |
| Age Summary · 18 To 34 | 119.0× |
| Age Summary · 35 To 64 | 436.0× |
| Age Summary · 65 Plus | 215 |
| Population under 18 | 322 |
| Median age | 39.5 years (vs Oklahoma 35.2y) |
Sources: Census ACS 5-Year 2024 — place-level B01001 query · Census ACS 5-Year 2023 · Refreshed 2026-04-29
Race, Ethnicity & Diversity
Of 1,092 residents, race / ethnicity breaks down by Census ACS counts (a person can identify with one or more groups). The Simpson diversity index is 0.31 (0 = single group, 1 = perfectly even distribution); this is read as somewhat diverse.
| White residents | 977 |
|---|---|
| Black residents | 2 |
| Hispanic or Latino residents | 224 |
| Diversity Index · Diversity index (Simpson) | 30.6% |
| Diversity Index · Diversity label | somewhat diverse |
| Diversity Index · Groups counted | 3 |
| Diversity Index · Largest group share | 81.2% |
| Black population | 0.2% (vs Oklahoma 5.5%) |
| Hispanic or Latino population | 23.9% (vs Oklahoma 12.3%) |
| White (non-Hispanic) population | 70.7% (vs Oklahoma 57.8%) |
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 (7)
Citizenship & Origin
Where residents were born and their citizenship status (Census ACS).
| Residents born in this state | 635 |
|---|---|
| Residents born in another state | 353 |
| Share born in this state | 58.2% |
| Share born in another state | 41.8% |
| Native-born U.S. citizens | 32.3% |
| Naturalized citizens | 9.5% |
| Total foreign-born residents | 147 |
Households & Family Composition
398 households. Averaging 2.8 people each — larger than the U.S. average of 2.5. 83% are family households — above the U.S. share of ~65%. Of 317 families, 42% are married couples with children.
| Children under 18 | 318 |
|---|---|
| Total families | 317 |
| Married couples with children | 133 |
| Single-parent households | 10 |
| Average household size | 2.79 |
| Women who gave birth (past year) | 8.1% |
| Grandparents living with grandchildren | 35 |
| Family households | 332 households (vs Oklahoma 16,590) |
| Households that are families | 83.4% (vs Oklahoma 61.1%) |
| Total households | 398 households (vs Oklahoma 23,671) |
Sources: Census ACS 5-Year 2023 · Refreshed 2026-04-12
Residential Stability & Migration
How long residents have lived here and where they came from. 14.7% moved within the county in the past year — the U.S. baseline is roughly 8–10%.
| Moved within the county (past year) | 14.7% |
|---|---|
| Migration · People moving in (annual) | 2,802 |
| Migration · People moving out (annual) | 2,780 |
| Migration · Net migration (in − out) | 22 |
| 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 | 162 |
|---|---|
| Disability rate | 13.3% |
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. 56 residents live in group quarters (5.1% of population).
| Living in group quarters | 56 |
|---|
Other
| Congressional District · District | 3 |
|---|---|
| Congressional District · Congress | 118th |
| Cdc Birth Rate · Fips | 40059 |
| Cdc Birth Rate · State Fips | 40 |
| Cdc Birth Rate · County Fips | 059 |
| Cdc Birth Rate · County | Harper |
| Cdc Birth Rate · Birth Rate | 25.4% |
| Cdc Birth Rate · Lower Ci | 15.40 |
| Cdc Birth Rate · Upper Ci | 39.30 |
| Cdc Mortality · Fips | 40059 |
| Cdc Mortality · County | Harper County |
| Cdc Mortality · Urban Rural | Noncore |
| Cdc Mortality · Total Deaths 2020 2023 | 113 |
| Cdc Vaccination · Fips | 40059 |
| Cdc Vaccination · County | Harper County |
| Cdc Vaccination · Dose1 Pop Pct | 52.3% |
| Cdc Vaccination · Series Complete Pct | 46.6% |
| Cdc Vaccination · Booster Pct | 44.5% |
| Cdc Vaccination · Population 2019 | 3,688 |
| Cdc Vaccination · Metro Status | Non-metro |
| Family Score · Score | 2.30 |
| Family Score · Schools | 2 |
| Family Score · Childcare Centers | 1 |
| Family Score · Children Pct | 29.5% |
| Family Score · Rating | limited |
| Town Summary · Key Facts | population 1,092, shrinking, family-oriented, middle-class, white collar |
| Town Summary · Population | 1,092 people (vs Oklahoma 63,420) |
| Town Summary · County | Harper County |
Sources: NCES school congressional district assignment · federal dataset cascade