The Koslowski surname
In the 2000 U.S. Census, 771 people carried this name — #28,994 among all U.S. surnames, about 1 in every 344,800 people counted.
Free to read. No account, no sign-up.
In France’s civil register
France’s register of deaths holds 58 people named Koslowski.
15 of them were born outside France. Those born in France came from 12 départements, most often Pas-de-Calais.
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 Switzerland’s population statistics
33 people named Koslowski live in Switzerland.
They live in 7 of Switzerland’s 26 cantons, most of all in Zurich.
Too few records to say where it concentrates region by region — these are plain counts, not shares.
Where they live today
Swiss Federal Statistical Office (FSO), «Surnames of the permanent resident population by canton», 2025, opendata.swiss · names with fewer than 3 bearers in a canton are not published.
In Poland’s population register
20 people named Koslowski have a registered home in Poland.
Of the 76 in Poland’s national register, these are the ones with a permanent address on file. They live in 3 of Poland’s 16 voivodeships, most of all in Kuyavian-Pomeranian.
Too few records to say where it concentrates region by region — these are plain counts, not shares.
Where 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.
Nearby in the index
Surnames next to Koslowski.
- Kornmann 166 · U.S. census
- Kos 1,621 · U.S. census
- Koscher 128 · U.S. census
- Koscielniak 516 · U.S. census
- Koscielny 165 · U.S. census
- Kosinski 2,589 · U.S. census
- Kosmala 258 · U.S. census
- Kosowski 546 · U.S. census
- Kost 3,161 · U.S. census
- Koster 6,137 · U.S. census
- Kostic 524 · U.S. census
- Kostka 1,291 · U.S. census
When the index is not enough
This page says where Koslowski 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.