thumb|The headquarters of Norwegian Confederation of Trade Unions, LO (Folkets Hus) at [[Youngstorget in Oslo]]
The Norwegian Confederation of Trade Unions (, LO) is a national trade union center, the largest and probably the most influential umbrella organization of labour unions in Norway. The 23 national unions affiliated to the LO have 1,038,502 members as of 2025. The majority of affiliated unions organizes traditional blue collar workers, but the largest affiliate is the Norwegian Union of Municipal and General Employees which makes up more than a third of all members. LO is affiliated to the ITUC and the ETUC.
It was named the Workers' National Trade Union (, AFL) from 1899 to 1957. Affiliated with the Labour Party throughout its history, several of LO's member unions have concurrently been member bodies in the Labour Party.
<!--Ingvald B. Aase served as treasurer from 1934 until his death in 1948.
-->
The organization owns the Norwegian Labour Movement Archives and Library.
Affiliates
Current affiliates
{| class="wikitable sortable"
! Union !! Abbreviation !! Founded !! Membership (2019)
|-
| Norwegian Authors' Union || || 2018 ||
|-
| Cabin Crew Union Norway|| NKF || 1978|| 402
|-
| Creo || Creo || 2001 || 9,533
|-
| Electrician and IT Workers' Union || El & IT || 1999 || 40,225
|-
| Industri Energi || IE || 2006 || 56,220
|-
| Labour Press Union|| APF || 1909 ||
|-
| National Union of Norwegian Locomotivemen || NLF || 1893 ||
|-
| Norwegian Airline Pilots Association || NF || 1977 ||
|-
| Norwegian Civil Service Union || NTL || 1947 || 53,087
|-
| Norwegian Engineers' and Managers' Association || FLT || 1951 || 21,935
|-
| Norwegian Manual Therapist Association|| NMF || 2006 ||
|-
| Norwegian Maritime Officers' Union || NSOF || 1995 || 7,106
|-
| Norwegian Players' Association || NISO || 1995 ||
|-
| Writers' Guild of Norway || NDF || 1938 ||
|-
| Norwegian Prison and Probation Officers' Union || NFF || 1918 ||
|-
| Norwegian Seafarers' Union || NSF || 1910 || 11,488
|-
| Norwegian Union of Food, Beverage and Allied Workers || NNN || 1923 || 28,221
|-
| Norwegian Union of General Workers || NAF || 1895 || 34,921
|-
| Norwegian Union of Military Officers || NOF || 1896 || 8,496
|-
| Norwegian Union of Municipal and General Employees || NUMGE || 2003 || 396,548
|-
| Norwegian Union of Railway Workers || NJF || 1892 ||
|-
| Norwegian Union of School Employees || SL || 1982 || 7,544
|-
| Norwegian Union of Social Educators and Social Workers || FO || 1992 || 31,000
|-
| Union of Employees in Commerce and Offices || HK || 1970 || 74,050
|-
| United Federation of Trade Unions || FF || 1988 || 164,679
|}
Former affiliates
{| class="wikitable sortable"
! Union !! Abbreviation !! Founded !! Left !! Reason not affiliated !! Membership (1924) !! Membership (1963) !! Membership (1991)
|-
| Garment Workers' Union || BAF || 1969 || 1988 || Merged into FF || N/A || N/A || N/A
|-
| Hotel and Restaurant Workers' Union || HRAF || 1931 || 2007 || Merged into FF || N/A || 9,345 || 16,036
|-
| National Union of District Police Officers || || 1914 || 1984 || Disaffiliated || || 800 || N/A
|-
| National Union of Postal Clerks || PLF || 1903 || 1977 || Merged into DNP || || 2,524 || N/A
|-
| Norwegian Air Force Officers' Union || || 1956 || || Disaffiliated || N/A || 1,660 || N/A
|-
| Norwegian Bakery and Confectionery Workers' Union || NBKF || 1893 || 1962 || Merged into NNN || 1,723 || N/A || N/A
|-
| Norwegian Barbers' and Hairdressers' Union || NBFF || || 1937 || Merged into NKF || 35 || N/A || N/A
|-
| Norwegian Cockpit Union || Cockpit || 2015 || 2016 || Merged into NF || N/A || N/A || N/A
|-
| Norwegian Fire Brigades Union || || 1909 || 1925 || Merged into NKF || || N/A || N/A
|-
| Norwegian Graphical Union || NGF || 1967 || 2006 || Merged into FF || N/A || N/A || 14,894
|-
| Norwegian Lithographic and Chemographic Union || || 1901 || 1967 || Merged into NGF || 480 || 1,837 || N/A
|-
| Norwegian Musicians' Union || NM || 1911 || 2001 || Merged into Creo || N/A || 1,271 || 2,248
|-
| Norwegian Nurses' Union || NVF || 1962 || 1992 || Merged into FO || N/A || N/A || 2,421
|-
| Norwegian Oil and Petrochemical Union || NOPEF || 1977 || 2006 || Merged into IE || N/A || N/A || 8,797
|-
| Norwegian Post and Communications Union || POSTKOM || 2000 || 2020 || Merged into NUMGE || N/A || N/A || N/A
|-
| Norwegian Post Organisation || DNP || 1977 || 2000 || Merged into POSTKOM || N/A || N/A || 15,442
|-
| Norwegian Social Workers' Union || NoSo || 1959 || 1992 || Merged into FO || N/A || N/A || 4,726
|-
| Norwegian Telecommunication and Data Workers' Union || TD || 1988 || 1998 || Merged into EL&IT || N/A || N/A || 16,387
|-
| Norwegian Telecommunication Organisation || DNTO || 1909 || 1988 || Merged into TD || || 1,638 || N/A
|-
| Norwegian Tobacco Workers' Union || NTF || 1910 || 1962 || Merged into NNN || 702 || N/A || N/A
|-
| Norwegian Tramway Union || || 1901 || 1921 || Merged into NKF || N/A || N/A || N/A
|-
| Norwegian Transport Workers' Union || NTF || 1896 || 2019 || Merged into FF || 4,802 || 21,609 || 15,803
|-
| Norwegian Union of Bookbinders and Cardboard Workers || NBKF || 1898 || 1967 || Merged into NGF || 1,246 || 4,556 || N/A
|-
| Norwegian Union of Bricklayers || NMF || 1900 || 1976 || Merged into NBIAF || 2,354 || 5,023 || N/A
|-
| Norwegian Union of Building Industry Workers || NBIAF || 1923 || 1988 || Merged into FF || 7,440 || 51,394 || N/A
|-
| Norwegian Union of Cantors and Organists || NKOF || 1904 || 2001 || Merged into Creo || N/A || N/A || 775
|-
| Norwegian Union of Chemical Industry Workers || NKIF || 1923 || 2006 || Merged into IE || 4,955 || 30,595 || 34,896
|-
| Norwegian Union of Child Welfare Educators || NBF || 1969 || 1992 || Merged into FO || N/A || N/A || 2,020
|-
| Norwegian Union of Clothing Workers || BAF || 1892 || 1969 || Merged into BAF || 1,080 || 14,259 || N/A
|-
| Norwegian Union of Customs Officials || || 1904 || || Disaffiliated || || 1,050 || N/A
|-
| Norwegian Union of Electricians and Power Station Officials || NEKF || 1918 || 1999 || Merged into EL&IT || 1,466 || 12,152 || 27,151
|-
| Norwegian Union of Forestry and Land Workers || NSLF || 1927 || 1988 || Merged into FF || N/A || 20,369 || N/A
|-
| Norwegian Union of Foundry Workers || || 1898 || 1960 || Merged into NJMF || 1,650 || N/A || N/A
|-
| Norwegian Union of Gold Workers || NGAF || 1909 || 1985 || Merged into NJMF || 435 || 1,033 || N/A
|-
| Norwegian Union of Hide and Leather Workers || || 1909 || 1973 || Merged into BAF || 426 || 1,300 || N/A
|-
| Norwegian Union of Iron and Metalworkers || NJMF || 1891 || 1988 || Merged into FF || 11,265 || 75,028 || N/A
|-
| Norwegian Union of Journeymen Watchmakers || || 1947 || 1983 || || N/A || 89 || N/A
|-
| Norwegian Union of Marine Pilots || || 1946 || || || N/A || 449 || N/A
|-
| Norwegian Union of Meat Industry Workers || NKIF || 1907 || 1970 || Merged into NNN || 524 || 4,024 || N/A
|-
| Norwegian Union of Municipal Employees || NKF || 1920 || 2003 || Merged into NUMGE || 5,835 || 59,831 || 200,320
|-
| Norwegian Union of Painters || || 1896 || 1923 || Merged into NBIAF || N/A || N/A || N/A
|-
| Norwegian Union of Paper Industry Workers || NPF || 1913 || 1988 || Merged into FF || 10,162 || 19,088 || N/A
|-
| Norwegian Union of Planing Workers || || 1911 || 1949 || Merged into NBIAF || 3,882 || N/A || N/A
|-
| Norwegian Union of Police || NPF || 1905 || 1997 || Merged into PF || || 2,213 || N/A
|-
| Norwegian Union of Postal Officials || DNP || 1884 || 1977 || Merged into DNP || || 3,127 || N/A
|-
| Norwegian Union of Postmen || NPF || 1901 || 2000 || Merged into POSTKOM || 959 || 4,426 || 14,498
|-
| Norwegian Union of Shoe Makers || || 1890 || 1969 || Merged into BAF || 1,934