Why the whole case rests on three years
Polish citizenship does not expire, and it does not fade because a family has lived across an ocean for a century. It ends on a particular day because of a particular event, and the law that decides this is older than most family stories: the Act of 20 January 1920 on the citizenship of the Polish State. Art. 11 ust. 1 pkt 1 took citizenship away at the moment a foreign one was acquired. So everything comes down to the day your ancestor was naturalised, and to what had already happened in the family by that day.
The second date matters because of Art. 13: the loss extended to the wife and to children under eighteen. A child who was seventeen on the day the father took the oath lost Polish citizenship with him. A child who had already turned eighteen kept it and carried it forward, to grandchildren and great-grandchildren. That is why the birth year of the next person in the line weighs exactly as much as the naturalisation year: without both, there is nothing to apply the law to.
The third date, your ancestor's own year of birth, does a different job. It proves the file you found is about him and not about a namesake. In American indexes the same first name and surname appears dozens of times, and without a birth year you will pay for someone else's file and then wait another year for the right one. The questionnaire asks for all three years because two of them carry the law and the third protects you from a costly mistake.
The good news. One document often settles two dates at once. An American naturalisation file created after 1906 gives both the date of birth and the date of naturalisation, and the law required the wife and minor children to be named on the petition and on the certificate itself. Who was in the family that day, and how old each of them was, is visible in the file. The legal core is set out in our section on citizenship by descent, and how confirmation differs from the Karta Polaka is explained in a separate article.
Where to go for each date
The table below gathers what was verified in September 2026 on the institutions' own websites: USCIS, the National Archives, Library and Archives Canada, IRCC and The National Archives. Fees and timescales change, so re-read them through the links further down before you file, but the structure of the search itself has been stable for decades.
| Country and period | Where to go | What it gives you | Cost and time |
|---|---|---|---|
| US, naturalised before 27 September 1906 | The court that granted it: municipal, county or state. Then the state archive or the local historical society | Often only a name, the court and a date: there were no standard forms yet | Whatever that archive charges |
| US, 1906–1956 | USCIS Genealogy Program, the C-File | Declaration of intention, petition and certificate: date and place of birth, port and date of arrival, wife and minor children | $30 online, $80 on paper |
| US, federal courts up to October 1991 | The National Archives (NARA) | Declarations of intention and petitions. Usually not the certificate of citizenship itself | NARA's own reproduction fees |
| Canada, 1915–1951 | The Library and Archives Canada index, built from the lists in the Canada Gazette | A name and the fact of naturalisation. The file itself is not held there | Free, searchable online |
| Canada, 1854 to the present | IRCC, Search of citizenship records | A letter giving the date the person became a citizen. It is not proof of citizenship | CAD 75 |
| UK, certificates up to 1980 | The Discovery catalogue, series HO 334 and HO 409 | The certificate: name, address, trade or occupation, country of origin, names of spouse and children | Searching is free, copies at the archive's rate |
| UK, 1981–1986 | A request through The National Archives' certificates page | The same certificate, but the archive does the searching | Search free, reply within 10 working days, certified copy £68.84 |
| UK, after 1 October 1986 | UK Visas and Immigration, not the archive | The certificate issued by the department | Home Office fees |
One figure in that table deserves separate attention, because it decides when you come back to the questionnaire. A US index search runs at about 191 business days and a copy of the file at about 300 business days, and this is not a queue in a bad month but the ordinary timescale USCIS publishes itself. In other words the American route takes a year and more, and it is worth starting before you gather anything else.
The US: 27 September 1906 splits the search in two
Before 27 September 1906 any court of record could naturalise: municipal, county, state or federal. There was no standard form, how much got written down depended on the clerk, and the volumes stayed wherever they were created. The National Archives says plainly that it holds almost nothing from local and state courts, only a handful of donated indexes. So if your ancestor became American in the nineteenth century, the search starts at a state archive or a county historical society, not at a federal agency.
After 27 September 1906 the picture changes completely. Standard forms appeared, and they are what make a file from this period the best document for our purpose: the forms called for the name, the date and place of birth, and the port and date of arrival. The 1906 law also required the naturalised citizen's wife and minor children to be listed on the petition and on the certificate. The file therefore answers the very question Art. 13 asks: who was a child that day, and how old were they.
From here, do not confuse two institutions, because they do not duplicate each other. The USCIS Genealogy Program holds five series: C-Files from 27 September 1906 to 31 March 1956, Alien Registration Forms AR-2 from 1 August 1940 to 31 March 1944, Registry Files from 2 March 1929, Visa Files from 1 July 1924, and A-Files opened from 1 April 1944. The National Archives holds something else: federal court records up to October 1991, meaning declarations of intention and petitions, usually without the certificate of citizenship. After October 1991 naturalisation moved from the courts to the agency, and everything since then is with USCIS.
The order of steps on the American route is fixed: first an index search on Form G-1041, and only then a copy of the file on Form G-1041A. Both cost the same, $30 filed online and $80 filed on paper. Do not skip the index even when a file number seems to be known from family papers: if the number does not match the name in the record, the money is not refunded. For the same fee, the index search tells you whether a file exists at all and gives you its exact number.
One more habit that saves months: do not search a single spelling of the surname. A family that left Galicia or Volhynia left behind documents filled in by different people in different languages, so the same surname can sit in an index in two or three forms, with the given name anglicised on top of that. If the obvious spelling returns nothing, that is not yet an answer: try the spellings pronunciation suggests, and cut the query down to the first letters of the surname plus a year and a city.
The program serves deceased subjects only. If the person you are asking about was born less than a hundred years before your request, you must attach proof of death: a copy of the death certificate, a Social Security Death Index entry, an obituary, a funeral programme or a photograph of the headstone. If they were born more than a hundred years ago, no proof is required, and this is the rare case where an old family history works in your favour.
Canada: the index is in one place, the file in another
The Canadian route is built differently, and one thing is worth understanding straight away: Library and Archives Canada holds lists, not files. The archive has three things: naturalisation records for Upper Canada from 1828 to 1850, covering almost three thousand people; citizenship registration files from the Montreal Circuit Court for 1851 to 1945, over eight thousand of them; and the naturalisation lists for 1915 to 1951. The last of these are publications: from 1921 to March 1932 they appeared in the Secretary of State's annual reports, and from April 1932 to April 1951 monthly in the Canada Gazette.
The archive is candid that not every name made it onto those lists, and that the reason is unknown. For your search that means something simple: an ancestor missing from the index is not evidence that he was never naturalised. It is a reason to go one step further, not to close the question. That step is IRCC, because most citizenship and naturalisation records from 1854 to the present are held by the department rather than the archive.
From IRCC you order a search of citizenship records, CAD 75. What comes back is a letter stating when the person became a Canadian citizen. For a deceased person the letter does not expire; for a living one it is valid for a year. IRCC states one thing plainly: the letter is not proof of Canadian citizenship, and a citizenship certificate exists for that purpose. This does not hurt us, because what the Polish file needs is the date, not proof of the foreign citizenship as such. The rules for requesting someone else's record are straightforward: if they died less than twenty years ago you need the death certificate, proof of your relationship and documents naming you as executor or administrator of the estate; if they died more than twenty years ago, a copy of your own identification is enough. Online applications are for your own record only, so an ancestor's record goes on paper. IRCC updates its processing time weekly on its own page, so quoting a number here would be meaningless: check it before you file.
The UK: search it yourself up to 1980, ask after that
The British route is the cheapest of the three, because most of the work can be done by yourself for nothing. The National Archives holds five series that matter here: HO 1 for 1801–1871 and HO 144 for 1872–1934 are case papers, HO 334 for 1870–1986 holds duplicates of the certificates themselves, HO 405 from 1934 holds case papers on foreign nationals, and HO 409 for 1908–1980 holds the indexes to the certificates. A certificate gives the name, address, trade or occupation, country of origin and the names of spouse and children, which for our purpose is no worse than an American file.
You search the Discovery catalogue by certificate number, or by surname followed by nat*. Certificates from 1870 to 1916 are also on Ancestry, while the 1913–1948 and 1949–1981 periods can be searched by name directly in Discovery. This is the case where an evening with a laptop replaces a paid request: if your ancestor was naturalised before 1981, there is a fair chance you will find the record yourself.
Then the boundaries begin. For certificates issued between 1981 and 1986 relating to someone born less than a hundred years ago, the archive searches on your behalf through its British citizenship certificates page: the search is free, the answer is promised within ten working days, and a certified copy costs £68.84 plus postage. Certificates issued after 1 October 1986 are not held by the archive at all, and for those you go to UK Visas and Immigration. The same line is drawn from the other side: Form NC, used to ask for a duplicate certificate, expressly does not cover certificates issued before October 1986.
Two British traps. First, between June 1969 and October 1986 the Home Office kept no duplicate certificates for foreign nationals, so for that period the only surviving evidence of naturalisation is the summary entries in the HO 409 indexes. Second, the HO 405 case papers are closed for a hundred years, access is opened on a freedom of information request, and only around forty per cent of them survive. A file missing from the catalogue is not proof that the naturalisation never happened.
What does the Polish side do with what you find?
The document you find is not the result, it is the raw material for the Polish procedure. The decision confirming citizenship is issued by the voivode for the place where the person lives or last lived in Poland, and where there is no such basis at all, the case goes to the Mazowieckie voivode. From abroad the application is filed through a Polish consul, who forwards it to the voivode.
Foreign documents are accepted only with a translation by a Polish sworn translator or a translation certified at a consulate. Documents from outside the European Union also need an apostille or consular legalisation, and that is done in the country that issued the document, not in Poland. Plan for it early: an apostille on an American file is far easier to arrange while you are still corresponding with the US than six months later from Warsaw.
The money and the time on the Polish side look like this. The voivode's decision costs 277 złoty, a power of attorney adds 17 złoty unless the representative is close family, and the consular fee for accepting and processing the application in the US is $118. The law gives the voivode six months from filing, not counting time spent waiting for other offices and archives to answer, and the Mazowieckie office itself warns that the rising number of applications is stretching that out. And here is the point that closes the circle: among the documents the voivode asks for is evidence that your grandfather or great-grandfather acquired a foreign citizenship. That is exactly the archival file you went to NARA, USCIS, IRCC or The National Archives for.
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Archival research feels boundless until you narrow it to one missing date. After that it is three steps, and the first one is done at your desk for nothing.
Write down the three years: your ancestor's birth, his naturalisation, and the birth of the next person in the line. The one you cannot fill in is your task. It often turns out that a single year is missing rather than the whole story, and that is a completely different amount of work.
In the US that is Form G-1041, in Canada the Library and Archives Canada list, in the UK the Discovery catalogue. An index search costs either nothing or $30, and it answers the question that matters: does the file exist. Ordering a copy blind means paying twice.
The American copy takes around 300 business days, and that time does not have to be empty. Birth records for the next person in the line, marriage certificates, your great-grandmother's Polish papers can all be gathered in parallel. When the date finally arrives from the archive, you will have a complete set in hand rather than the start of a new search.
Frequently asked questions
My ancestor was naturalised before 1906. Where do I look?
At the court that granted it, or at the archive its volumes went to, which is usually a state archive or a local historical society. Before 27 September 1906 any court of record could naturalise, there were no standard forms, and the National Archives says plainly that it holds almost nothing from local and state courts. Expect less information in these records: often a name, the court and a date, with no place of birth.
Can I order the file of someone who is still alive?
No. The USCIS Genealogy Program serves deceased subjects. If the person was born less than a hundred years before your request, you attach proof of death: a copy of the death certificate, a Social Security Death Index entry, an obituary, a funeral programme or a photograph of the headstone. If they were born more than a hundred years ago, no proof of death is needed.
How long does an American file really take?
On the figures USCIS updated on 7 January 2025, an index search on Form G-1041 takes about 191 business days and a copy of the file on Form G-1041A about 300 business days. Together that is more than a year, which is why the American request is the one to file first while you gather everything else in parallel.
Does the Canadian letter from IRCC prove my ancestor's citizenship?
No, and IRCC says so directly: the letter from a search of citizenship records is not proof of Canadian citizenship, and a citizenship certificate exists for that. But the Polish procedure needs something else, the date on which your ancestor acquired a foreign citizenship, and that is precisely what the letter gives.
My ancestor was naturalised in the UK after October 1986. What now?
The National Archives does not hold those certificates; the line falls on 1 October 1986. For anything after that date you go to UK Visas and Immigration. The rule mirrors itself from the other direction: Form NC, used to request a duplicate certificate, does not cover certificates issued before October 1986.
The archive replied that there is no record. Is that the end?
No, and it is often good news. If there was no naturalisation, Art. 11 ust. 1 pkt 1 of the 1920 act never operated and the citizenship in your line was never broken on that ground. A negative answer is therefore a document in its own right: IRCC states in the letter when there is no record, and the American index search exists precisely to tell you whether a file is there at all. From there you check the other grounds of loss: foreign military service or public office abroad under Art. 11 ust. 1 pkt 2, and on the female line marriage to a foreigner under Art. 10.