Costopoulos
surname · Latin script
Costopoulos is a surname written in the Latin script, with more bearers in Congo - Kinshasa than in any other country. In Guernsey it is the 42nd most common surname.
- GRGreece≈1 in 18Kas Kostopoulos(inferred from the name graph)
- USUnited States1 in 708Kas Kostopoulos
- GGGuernsey≈1 in 2.5K
carrying the name, as counted by its national register where one exists and as Mondonomo estimates it elsewhere (marked ≈ and "est." on hover). Where a country counts another spelling of the name rather than Costopoulos itself, the figure is that spelling’s, and it is named. One hue, darker where it is more common; hover a country for its figure.
- Congo - Kinshasa (inferred from the name graph)
- 2 (measured from records)
- Sources
- 162 (measured from records)
- ≈1 in 2.5K (inferred from the name graph)
≈730 named Kostopoulos, est.
recorded for this name
Highest-authority source
Guernsey, est.
measured from records inferred from the name graph
Spellings & scripts(measured from records)
2 other spellings are counted as the same name:
Locally spelled Kostopoulos in US United States, AU Australia, CA Canada and 3 more and Κωστοπουλος in GR Greece.
Spellings marked ● are how people bearing the name write it in our records, and ○ marks a model's transliteration; click a spelling to open its page.
Meaning & origin
No verified etymology recorded for this name yet — the entries below are drawn from usage statistics and the name graph.
Attested in 1 language in the etymology graph.
Where in the world(measured from records)
Costopoulos counted together with the spellings and other-language forms grouped with it. Where a register counted another spelling, the row names it.
Sorted by bearers: national registers' counts, and Mondonomo's estimates (≈, est.) where no register counts.
| Country | Most common spelling | Sources | ||||
|---|---|---|---|---|---|---|
| CD Congo - Kinshasa | — | ≈730 est. | ≈1 in 139K | — | Kostopoulos | 1 |
| GR Greece | #423 | ≈590 est. | ≈1 in 18K | 20 | Κωστοπουλος | 79 |
| US United States | — | 470as Kostopoulos | 1 in 708K | 470 | Kostopoulos | 162 |
| CA Canada | — | ≈150 est. | ≈1 in 251K | — | Kostopoulos | 45 |
| AU Australia | — | ≈140 est. | ≈1 in 178K | — | Kostopoulos | 50 |
| NO Norway | — | 36as Kostopoulos | 1 in 152K | 36 | Kostopoulos | 9 |
| CY Cyprus | #897 | ≈30 est. | ≈1 in 42K | — | Kostopoulos | 9 |
| GG Guernsey | #42 | ≈27 est. | ≈1 in 2.5K | — | Costopoulos | 1 |
Exact figures are national registers' own counts, while figures marked ≈ and est. are Mondonomo’s estimates, counted from our sources and calibrated against those registers; hover one for how far to trust it in that country. A dash means neither exists.
Registers cited: Census Bureau — Surname Frequency 2010; Διαύγεια — directory of signing officials (organization → signers); SSB — Navnesøk (name-search service, living population). Figures without a register are Mondonomo estimates; see Methodology.
Country figures for a list of names, at full precision, are available under licence rather than by scraping this table (how that works).
Notable people with this name(measured from records)
- Yannis Kostopoulosb. 1938GRGreek banker
The ten people covered by the most Wikipedia language editions — a proxy for cross-cultural notability, which favours historical and Western figures over equally prominent contemporary ones — shown by birth year. Source: Wikidata (CC0).
Evidence(measured from records)
Attested in 6 sources across 2 countries.
| Country | Register | Year | Count | Rank |
|---|---|---|---|---|
| US United States | Census Bureau — Surname Frequency 2010 | 2010 | 169 | #105,600 |
| US United States | Census Bureau — Surname Frequency 2000 | 2000 | 160 | #103,706 |
| US United States | Census Bureau — Surname Frequency 2020 | 2020 | 158 | #116,774 |
| US United States | wru Name Dictionary — US surnames, Census 2010 subset (Khanna et al.) | — | — | — |
Reference works 1
- Wikidata name items (native-script + romanized given/family names)
These works list the name; their figures are licensed and are not reproduced here.
Register rows as of the 2026-10-09 data build.
Frequently asked questions
- In which country does Costopoulos have the most bearers?
- Mondonomo estimates about 731 people named Kostopoulos in Congo - Kinshasa, more than in any other country we hold.
- How common is the name Costopoulos?
- In the United States, the national register counted 470 people named Kostopoulos in 2010, about 1 in 708 thousand residents.
- How common is Costopoulos compared with other names?
- In Guernsey, Costopoulos is the 42nd most common surname of 45 surnames recorded there.
What do you want to know about Costopoulos?
Nobody replies to these one by one, but what readers ask decides what these pages answer next.
Query this name via API
curl https://api.mondonomo.ai/api/v1/name-graph/costopoulosThe same payload this page is built from: spellings and scripts, countries and languages, related names, and the registers that attest the form. Rate-limited for casual use; a free API key gives 1,000 requests a day, and bulk access is licensed separately.
About this data
measured from records inferred from the name graph machine-generated
These figures come from the data snapshot of and will change as it is rebuilt.
Statistics are aggregated from the Mondonomo name corpus; related names and etymology are inferred from the name graph; pronunciation and any machine-marked transliterations are model-generated. Read how the numbers are made, including their known failure modes, and where the data comes from.
Reference works we consult — surname dictionaries, official name registers, Wikidata and Wiktionary — are named directly, beside the claims they support. The per-country source counts also include datasets of person records: we publish how many there are and their authority tier, but not their names.
Cite this page Mondonomo, “Costopoulos” — the 42nd most common surname in Guernsey. Data snapshot 2026-10-10.