| 16/1993 : Immigrants and Emigrants (Amendment) |
| 42/1998 : Immigrants and Emigrants (Amendment) |
| 31/2006 : Immigrants and Emigrants (Amendment) |
| 07/2015 : Immigrants and Emigrants (Amendment) |
| 27/2021 : Immigrants and Emigrants (Amendment) |
| 57/1971 : Imports and Export Regulation (Validation) |
| 01/1969 : Imports and Exports (Control) |
| 48/1985 : Imports and Exports (Control) (Amendment) |
| 28/1987 : Imports and Exports (Control) (Amendment) |
| 14/1965 : Imposition of Civic Disabilities (Special Provisions) |
| 13/1964 : Income Tax Evasion and Non-disclosure of Profits and Income |
| 12/2005 : Increase of Fines |
| 20/1982 : Indemnity |
| 60/1988 : Indemnity (Amendment) |
| 47/1981 : Indo – Ceylon Agreement (Implementation) (Amendment) |
| 43/1971 : Indu – Ceylon Agreement Implementation (Amendment) |
| 36/1969 : Industrial Development |
| 39/1968 : Industrial Disputes (Amendment) |
| 32/1990 : Industrial Disputes (Amendment) |
| 56/1999 : Industrial Disputes (Amendment) |
| 11/2003 : Industrial Disputes (Amendment) |
| 21/2008 : Industrial Disputes (Amendment) |
| 39/2011 : Industrial Disputes (Amendment) |
| 22/2022 : Industrial Disputes (Amendment) |
| 24/2022 : Industrial Disputes (Amendment) |
| 13/2003 : Industrial Disputes (Hearing and Determination of Proceedings) (Special Provisions) |
| 37/1968 : Industrial Disputes (Special Provisions) |
| 53/1973 : Industrial Disputes (Special Provisions) |
| 19/2022 : Industrial Disputes (Special Provisions) |
| 46/1990 : Industrial Promotion |
| 51/1999 : Industrial Security Foundation (Sri Lanka) (Incorporation) |
| 27/2003 : Information and Communication Technology |
| 33/2008 : Information and Communication Technology (Amendment) |
| 04/1963 : Inland Revenue |
| 28/1979 : Inland Revenue |
| 38/2000 : Inland Revenue |
| 10/2006 : Inland Revenue |
| 24/2017 : Inland Revenue |
| 26/1968 : Inland Revenue (Amendment) |
| 06/1969 : Inland Revenue (Amendment) |
| 31/1971 : Inland Revenue (Amendment) |
| 33/1971 : Inland Revenue (Amendment) |
| 01/1974 : Inland Revenue (Amendment) |
| 15/1974 : Inland Revenue (Amendment) |
| 18/1975 : Inland Revenue (Amendment) |
| 16/1976 : Inland revenue (Amendment) |
| 24/1980 : Inland Revenue (Amendment) |
| 40/1981 : Inland Revenue (Amendment) |
| 27/1982 : Inland Revenue (Amendment) |
| 43/1983 : Inland Revenue (Amendment) |
| 14/1984 : Inland Revenue (Amendment) |
| 16/1985 : Inland Revenue (Amendment) |
| 56/1985 : Inland Revenue (Amendment) |
| 27/1986 : Inland Revenue (Amendment) |
| 08/1987 : Inland Revenue (Amendment) |
| 08/1988 : Inland Revenue (Amendment) |
| 31/1988 : Inland Revenue (Amendment) |
| 11/1989 : Inland Revenue (Amendment) |
| 22/1990 : Inland Revenue (Amendment) |
| 42/1990 : Inland Revenue (Amendment) |
| 49/1991 : Inland Revenue (Amendment) |
| 63/1992 : Inland Revenue (Amendment) |
| 35/1993 : Inland Revenue (Amendment) |
| 21/1994 : Inland Revenue(Amendment) |
| 27/1995 : Inland Revenue (Amendment) |
| 16/1996 : Inland Revenue(Amendment) |
| 24/1997 : Inland Revenue (Amendment) |
| 52/1998 : Inland Revenue (Amendment) |
| 41/1999 : Inland Revenue (Amendment) |
| 08/2001 : Inland Revenue (Amendment) |
| 10/2002 : Inland Revenue(Amendment) |
| 19/2003 : Inland Revenue (Amendment) |
| 37/2003 : Inland Revenue (Amendment) |
| 12/2004 : Inland Revenue (Amendment) |
| 08/2005 : Inland Revenue (Amendment) |
| 10/2007 : Inland Revenue (Amendment) |
| 09/2008 : Inland Revenue (Amendment) |
| 19/2009 : Inland Revenue (Amendment) |
| 22/2011 : Inland Revenue(Amendment) |
| 08/2012 : Inland Revenue (Amendment) |
| 18/2013 : Inland Revenue (Amendment) |
| 08/2014 : Inland Revenue (Amendment) |
| 09/2015 : Inland Revenue (Amendment) |
| 10/2021 : Inland Revenue (Amendment) |
| 04/2023: Inland Revenue (Amendment) |
| 14/2023 : Inland Revenue (Amendment) |
| 19/1975 : Inland Revenue (Change of Designations of Certain Officers) |
| 10/2004 : Inland Revenue (Regulation of Amnesty) |
| 07/2002 : Inland Revenue (Special Provisions) |
| 10/2003 : Inland Revenue (Special Provisions) |
| 31/2003 : Inland Revenue (Special Provisions)(Amendment) |
| 14/1990 : Inland Trust Receipts |
| 22/2024 : Inland Trust Receipts (Amendment) |
| 07/1958 : Inspector of Labour (Change of Designation) |
| 38/2011 : Institute of Applied Statistics, Sri Lanka (Incorporation) |
| 48/1992 : Institute of Automotive Engineers of Sri Lanka (Incorporation) |
| 26/1979 : Institute of Bankers of Sri Lanka (Incorporation) Act |
| 22/1984 : Institute of Biology, Sri Lanka (Incorporation) |
| 23/2009 : Institute of Certified Management Accountants of Sri Lanka |
| 34/1975 : Institute of Chartered Accountants (Amendment) |
| 15/1998 : Institute of Chartered Accountants (Amendment) |
| 23/1959 : Institute of Chartered Accountants Act |
| 34/2024 : Institute of Chartered Shipbrokers of Sri Lanka (Incorporation) |
| 15/1972 : Institute of Chemistry, Ceylon |
| 03/1980 : Institute of Corporation Lawyers (Amendment) |
| 24/2008 : Institute of Dharuth Thowheed Assalafiyya (Incorporation) |
| 11/2000 : Institute of Engineering Diplomates Sri Lanka (Incorporation) (Amendment) |
| 64/1992 : Institute of Engineering Diplomates, Sri Lanka (Incorporation) |
| 17/1968 : Institute of Engineers, Ceylon |
| 03/1996 : Institute of Engineers, Ceylon (Amendment) |
| 01/2020 : Institute of Environmental professionals, Sri Lanka (Incorporation) |
| 05/1997 : Institute of Fundamental Studies (Amendment) |
| 55/1981 : Institute of Fundamental Studies, Sri Lanka |
| 25/2014 : Institute of Fundamental Studies, Sri Lanka (Amendment) |
| 03/2014 : Institute of Geology, Sri Lanka (Incorporation) |
| 67/1988 : Institute Of Management Of Sri Lanka (Incorporation) |
| 55/1998 : Institute Of Mass Communication (Incorporation) |
| 24/1976 : Institute of Personnel Management Sri Lanka |
| 31/2018 : Institute of Personnel Management, Sri Lanka (Amendment) |
| 12/1986 : Institute Of Physics, Sri Lanka (Incorporation) |
| 53/1988 : Institute of Policy Studies of Sri Lanka |
| 09/1999 : Institute of Policy Studies of Sri Lanka (Amendment) |
| 01/2014 : Institute of Policy Studies of Sri Lanka (Amendment) |
| 73/2009 : Institute of Project Managers (Incorporation) Sri Lanka |
| 20/2007 : Institute of Quantity Surveyors, Sri Lanka (Incorporation) |
| 42/1980 : Institute of Sinhala Culture (Incorporation) Act |
| 03/1981 : Institute of Supply and Materials Management, Sri Lanka |
| 21/1969 : Institute of Surveying and Mapping |
| 23/1986 : Institute Of Town Planners, Sri Lanka (Incorporation) |
| 33/1975 : Institute of Valuers of Sri Lanka |
| 09/2019 : Institute of Valuers of Sri Lanka (Amendment) |
| 44/1988 : Institute Of Western Music And Speech (Incorporation) |
| 22/1979 : Insurance (Special Provisions) |
| 44/1986 : Insurance (Special Provisions) (Amendment) |
| 02/1961 : Insurance Corporation |
| 43/1986 : Insurance Corporation (Amendment) |
| 36/2003 : Intellectual Property |
| 07/2018 : Intellectual Property (Amendment) |
| 08/2021 : Intellectual Property (Amendment) |
| 08/2022 : Intellectual Property (Amendment) |
| 40/1968 : Interim Devaluation Allowance of Employees |
| 05/2018 : International Convention for the Protection of All Persons from Enforced Disappearance Act |
| 56/2007 : International Covenant on Civil and Political Rights (ICCPR) |
| 07/1961 : International Development Association Agreement |
| 30/2000 : International Friendship, Educational Cultural and Social Services Association (Incorporation) |
| 32/2024 : International Institute of Theravadha (Incorporation) |
| 06/1985 : International Irrigation Management Institute |
| 50/2000 : International Irrigation Management Institute (Amendment) |
| 43/1999 : International Shanthee Dharma Organisation (Incorporation) |
| 05/2000 : International Volunteer Friendship Association (Incorporation) |
| 07/1982 : International Winged Bean (Dambala) Institute |
| 18/1972 : Interpretation (Amendment) |
| 29/1974 : Interpretation (Amendment) |
| 48/1968 : Irrigation (Amendment) |
| 23/1983 : Irrigation (Amendment) |
| 34/1990 : Irrigation (Amendment) |
| 13/1994 : Irrigation(Amendment) |
| 34/1984 : Isha-athul Islam Home For The Orphans (Incorporation) |
| 16/2000 : Islamic Service Society, Akurana (Incorporation) |
| 43/1991 : Islamic Youth Front (Incorporation) |