The Koc surname
In the 2010 U.S. Census, 566 people carried this name — #38,948 among all U.S. surnames, about 1 in every 526,300 people counted. That is up 30% from 435 in 2000.
In Poland’s population register
3,913 people named Koc have a registered home in Poland.
Of the 4,458 in Poland’s national register, these are the ones with a permanent address on file. They live in all 16 of Poland’s voivodeships, most of all in Masovian.
Where it concentrates, on the mapWhere they live today
PESEL register, Ministry of Digital Affairs of Poland (dane.gov.pl) — CC0 · living people by voivodeship of permanent residence, 20 January 2026.
In Belgium’s population register
At least 727 people named Koc live in Belgium.
Statbel only publishes a name in a municipality when five or more people there share it, so the real number is higher. Most of them live in Brussels-Capital.
Where it concentrates, on the mapWhere they live today
Statbel (Statistics Belgium), family names of the population by municipality, 1 January 2026 — CC BY 4.0.
In Switzerland’s population statistics
565 people named Koc live in Switzerland.
They live in 20 of Switzerland’s 26 cantons, most of all in Zurich.
Where it concentrates, on the mapWhere they live today
Swiss Federal Statistical Office (FSO), «Surnames of the permanent resident population by canton», 2025, opendata.swiss/en/dataset/nachnamen-der-standigen-wohnbevolkerung-nach-kanton3 · names with fewer than 3 bearers in a canton are not published.
In France’s civil register
France’s register of deaths holds 134 people named Koc.
Most of them — 106 — were born outside France. Those born in France came from 15 départements, most often Val-d’Oise.
Too few records to say where it concentrates region by region — these are plain counts, not shares.
Where they were born
Fichier des personnes décédées, INSEE — Licence Ouverte 2.0 · deaths recorded in France since 1970, by place of birth.
In the Nordic population registers
367 people named Koc are counted in Sweden and Finland.
Sweden’s figure is from 31 December 2022, the last count Statistics Sweden published. Finland counts its citizens, at home or abroad.
Counted, by country
Own calculations based on data from Statistics Sweden (SCB), surnames with at least two bearers, 31 December 2022 — CC BY 4.0 (names with 20 or more bearers shown) · Digital and Population Data Services Agency (DVV), Finland, surname statistics, August 2026 — CC BY 4.0.
In print
Koc in American newspapers,
1868–1941.
Chronicling America, Library of Congress — digitised newspapers in the public domain · 52,201 pages in all carry the name.
Who carried it
People named Koc,
with a public archive behind them.
-
Adam Koc 1891–1969 · politician -
Leon Koc 1892–1954 · military officer -
Tadeusz Koc 1913–2008 · military officer -
Maria Koc 1964– · politician -
Cem Koç 1970– · graphic designer -
Pavel Koc 1896–
Wikidata and Wikimedia Commons (CC0) · 25 lives in all are documented under this name.
Nearby in the index
Surnames next to Koc.
When the index is not enough
This page says where Koc is.
A volume says what happened to it.
Every page in the index is free and stays free. The Heritage Volume is the long form: the full paper trail, the arms, the crossing — bound, and yours.