Editing National identification number (section)

=== Denmark ===
{{Main|Personal identification number (Denmark)}}
A Personal Identification Number (Da. ''personnummer''<ref name=":0" />'','' informally and more commonly called ''CPR,'' from the registers' name ''Det <u>C</u>entrale <u>P</u>erson<u>r</u>egister'') in Denmark is used in dealings with public agencies, from health care to the tax authorities. It is also used as a customer number in banks and insurance companies. People must be registered with a CPR number if they reside in Denmark, if they own property or if they pay tax.

In Denmark, there has been a systematic registration since 1924, however it was in 1968 that the electronic CPR register was established.<ref name=":0">{{cite web |url=http://www.cpr.dk/cpr/site.aspx?p=16 |title= Om CPR-kontoret - CPR|website=www.cpr.dk |archive-url=https://web.archive.org/web/20120731034613/http://www.cpr.dk/cpr/site.aspx?p=16 |archive-date=31 July 2012}}</ref>

In the 1980s, the electronic system was exported to Kuwait, Jamaica, Malaysia, Thailand, Romania, Cyprus, Estonia, Latvia, Slovakia, and Saint Petersburg.<ref>{{cite web |url=http://datamuseum.dk/site_dk/20101026/CPR_20101026.pdf |title=CPR's udvikling gennem mere end 40 ar |publisher=Datamuseum.dk |access-date=2014-03-08 |archive-date=2013-10-29 |archive-url=https://web.archive.org/web/20131029191717/http://datamuseum.dk/site_dk/20101026/CPR_20101026.pdf |url-status=live }}</ref>

The CPR number is a ten-digit number with the format DDMMYY-SSSS, where DDMMYY is the date of birth and SSSS is a sequence number. The first digit of the sequence number encodes the century of birth (so that centenarians are distinguished from infants, 0–4 in odd centuries, 5–9 in even centuries), and the last digit of the sequence number is odd for males and even for females.

Prior to 2007, the last digit was also a check digit such that less than 240 SSSS values were available for any given combination of gender and date of birth, but due to an administrative practice of assigning 1 January and similar dates for immigrants with unknown date of birth, any SSSS value consistent with gender and century of birth may now be issued, even for birth dates prior to 2007.

Companies and other taxable non-humans are issued an eight-digit "CVR" number which is a mostly sequential number, there is no defined rule preventing the issuance of a CVR number with the same digits as a CPR number of an unrelated person, so the type of number must always be indicated, but CPR are always 10-digit and CVR 8-digit. VAT registration numbers for Danish companies are simply "DK" followed by the CVR number, but far from all CVR numbered entities are VAT registered (companies with no need for a VAT number, such as holding companies, typically do not request a VAT registration for their CVR).

Government entities are numbered in a variety of ways, but since 2003 all government entities (however small) now have EAN numbers for billing purposes. Some Government entities also have CVR numbers. Only one Government Entity (the Queen) has a CPR number.

The CPR number gives government agencies access to state-controlled databases with information about the person. The information includes: The person's marital status and spouse, parents, children, current and former addresses, the cars the person has owned, the criminal record and other information about the person.

Foreigners who are not eligible to get a CPR-number, but who need one, includes persons who have witnessed a crime, persons who have been charged with a crime, or are victims of a crime. These persons are registered with a CPR-number with the format: DDMMYY-XXXX where XXXX are four letters instead of four numbers.