The Siess surname
In the 2010 U.S. Census, 451 people carried this name — #47,107 among all U.S. surnames, about 1 in every 666,700 people counted. That is down 3% from 466 in 2000.
In France’s civil register
France’s register of deaths holds 121 people named Siess.
6 of them were born outside France. Those born in France came from 12 départements, most often Bas-Rhin.
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 Poland’s population register
51 people named Siess have a registered home in Poland.
Of the 57 in Poland’s national register, these are the ones with a permanent address on file. They live in 8 of Poland’s 16 voivodeships, most of all in Masovian.
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.
In Switzerland’s population statistics
39 people named Siess live in Switzerland.
They live in 4 of Switzerland’s 26 cantons, most of all in Jura.
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.
Nearby in the index
Surnames next to Siess.
- Siegfried 3,688 · U.S. census
- Siegler 1,618 · U.S. census
- Siegrist 2,681 · U.S. census
- Siegwald 118 · U.S. census
- Sieradzki 320 · U.S. census
- Sierra 35,770 · U.S. census
- Sigal 598 · U.S. census
- Sigala 4,817 · U.S. census
- Sigalas 136 · U.S. census
- Sigel 1,339 · U.S. census
- Sigler 8,992 · U.S. census
- Signor 999 · U.S. census
When the index is not enough
This page says where Siess 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.