Casual vacancies in the Dewan Undangan Negeri (state legislative assembly) are filled by by-elections, which may occur when a member of the Dewan Undangan Negeri dies, resigns or for some other reason. Members of the Dewan Undangan Negeri normally tender the resignation to the Speaker. The Speaker has a discretion as to when to call a by-election and may not call one at all, for example, if a general election or a state election is imminent.
Brackets around a date indicate that the candidate was unopposed when nominations closed. These candidates were declared "elected unopposed" with effect from the date of the closing of nominations, and there was no need to hold a by-election.
2022–present By-election State Assembly Date Incumbent Party Winner Party CauseChupingPerlisCancelledSaad SemanPN (PAS)colspan=3 Declared vacant by the Speaker due to change of party allegiance. However, SPR did not hold a by-election.BintongPerlisCancelledFakhrul Anwar Ismailcolspan=3 Guar SanjiPerlisCancelledMohd Ridzuan Hashimcolspan=3 LamagSabah24 January 2026Bung Moktar Radin BN (UMNO)Mohd Ismail Ayob BN (UMNO)Death (kidney failure and lung infection)MelalapSabahCancelledPeter AnthonyKDMcolspan=3 Disqualification (sentenced to jail for falsying documents)Ayer KuningPerak26 April 2025Ishsam Shahruddin BN (UMNO)Mohamad Yusri Bakir BN (UMNO)Death (acute coronary syndrome)Sungai Sibuga Sabah CancelledMohamad Hamsan Awang Supain colspan=3 Death (kidney complications)MahkotaJohor28 September 2024Sharifah Azizah Syed Zain Syed Hussein Syed Abdullah BN (UMNO)Death (internal bleeding)Nenggiri Kelantan17 August 2024Mohd Azizi Abu NaimPN (BERSATU)Mohd Azmawi Fikri Abdul Ghani BN (UMNO)Disqualification (change of political allegiance) Sungai Bakap Penang6 July 2024Nor Zamri LatiffPN (PAS)Abidin IsmailPN (PAS)Death (inflammation of stomach) Kuala Kubu Baharu Selangor11 May 2024Lee Kee Hiong PH (DAP) Pang Sock Tao PH (DAP) Death (ovarian cancer) Jepak Sarawak4 November 2023Talib Zulpilip GPS (PBB) Iskandar Turkee GPS (PBB)Death (kidney complications)PelangaiPahang7 October 2023Johari Harun BN (UMNO)Amizar Abu Adam BN (UMNO)Death (plane crash) in Elmina, Selangor.Simpang JeramJohor 9 September 2023Salahuddin Ayub PH (AMANAH)Nazri Abdul Rahman PH (AMANAH)Death (brain hemorrhage)BelantekKedahCancelledMohd Isa ShafiePN (PAS) colspan=3 Death (Pneumonia, Endocarditis and Pyelonephritis). However, SPR did not hold a by-election.BertamPenangKhaliq Mehtab Mohd IshaqPN (BERSATU)colspan=3 Declared vacant by the Speaker due to change of party allegiance. However, SPR did not hold a by-election.Seberang JayaAfif Bahardincolspan=3 Sungai AchehZulkifli Ibrahimcolspan=3 Telok BahangZolkifly Mohd Lazimcolspan=3 Batang KaliSelangorHarumaini OmarPEJUANG colspan=3 Declared vacant by the Speaker due to long absence without the leave of the Speaker. However, SPR did not hold a by-election.GurunKedahJohari Abdul PH (PKR)colspan=3 Resignation on appointment as Speaker of Dewan Rakyat. However, SPR did not hold a by-election.TiomanPahang7 December 2022Mohd Johari Hussain BN (UMNO)Mohd Johari Hussain BN (UMNO)The election was postponed from the original date because of the death of one of the candidates after the nomination day of 2022 Pahang state election.
2018–22
By-election State Assembly Date Incumbent Party Winner Party CauseKempasJohorCancelled Osman SapianPN (BERSATU) colspan=3 Death (stroke)BalehSarawakJames Jemut MasingGPS (PRS) colspan=3 Death (heart attack)MelorKelantanMd Yusnan YusofPN (PAS) colspan=3 Death (heart attack)BugayaSabah19 November 2022Manis Muka Mohd Darah WARISANJamil Hamzah WARISANDeath (kidney ailment) SlimPerak Mohd. Khusairi Abdul Talib BN (UMNO)Mohd Zaidi Aziz BN (UMNO)Death (heart attack)ChiniPahangAbu Bakar HarunMohd Sharim Md ZainDeath (heart attack)PujutSarawakCancelledTing Tiong Choon PH (DAP)colspan=3 Declared vacant by the Federal Court based on having dual citizenship decision to declare disqualification. However, SPR did not hold a by-election. RantauNegeri SembilanMohamad Hasan BN (UMNO)Mohamad Hasan BN (UMNO)Uncontested election nullified (Election petition)SemenyihSelangorBakhtiar Mohd Nor PH (BERSATU)Zakaria HanafiDeath (heart Attack)Seri SetiaShaharuddin Badaruddin PH (PKR)Halimey Abu Bakar PH (PKR)Death (colon cancer)BalakongEddie Ng Tien Chee PH (DAP)Wong Siew Ki PH (DAP)Death (traffic collision)Sungai KandisMat Shuhaimi Shafiei PH (PKR)Mohd Zawawi Ahmad Mughni PH (PKR)Death (lymphoma)
2013–18
By-election State Assembly Date Incumbent Party Winner Party CausePaginatanSabahCancelledSiringan Gubat BN (UPKO)colspan=3 Death (heart attack)ApasTawfiq Abu Bakar Titingan BN (UMNO)colspan=3 Death (colon cancer)LeparPahangMohd. Shohaimi Jusohcolspan=3 Death (diabetes)LenggengNegeri SembilanIshak Ismailcolspan=3 Death (heart attack)NenggiriKelantanMat Yusoff Abd. Ghanicolspan=3 Declared vacant by the Speaker based on the Insolvency Department’s decision to declare him a bankrupt. However, SPR did not hold a by-election. TungkuSabahMohd. Suhaili Saidcolspan=3 Death (liver cancer)Tanjong DatuSarawakAdenan Satem BN (PBB)Jamilah Anu BN (PBB)Death (heart attack)Sungai Air TawarSelangorCancelledKamarol Zaki Abdul Malik BN (UMNO)colspan=3 Death (heart attack)ChempakaKelantanNik Abdul Aziz Nik Mat PASAhmad Fathan Mahmood PASDeath (prostate cancer)Pengkalan KuborKelantanNoor Zahidi Omar BN (UMNO)Mat Razi Mat Ail BN (UMNO)Death (liver cancer)Bukit AssekSarawakCancelledWong Ho Leng DAPcolspan=3 Death (brain cancer)BalingianAbdul Taib Mahmud BN (PBB)Yussibnosh Balo BN (PBB)Resignation on appointment as Yang di-Pertua Negeri of SarawakKajangSelangorLee Chin Cheh PKRWan Azizah Wan Ismail PKRResignation (Kajang Move)Sungai LimauKedahAzizan Abdul Razak PASMohd Azam Abd Samat PASDeath (cardiac arrest)Kuala BesutTerengganuA. Rahman Mokhtar BN (UMNO)Tengku Zaihan Che Ku Abd Rahman BN (UMNO)Death (lung cancer)
2008–13
By-election State Assembly Date Incumbent Party Winner Party CauseChenorPahangCancelledTan Mohd Aminuddin Ishak BN (UMNO)Death (food poisoning)Kuala NerangKedahSyed Sobri Syed Hashim Declared vacant by the Speaker based on the Insolvency Department's decision to declare him a bankrupt. However, SPR did not hold a by-election.JoholNegeri SembilanRoslan Mohd Yusof Death (lung)LenduMalaccaIdderris Kassim colspan=3 Death (colon cancer)Bukit GasingSelangorEdward Lee Poh Lin DAPcolspan=3 Death (colon cancer)MerlimauMalacca6 March 2011Mohamad Hidhir Abu Hassan BN (UMNO)Roslan Ahmad BN (UMNO)Death (heart attack)KerdauPahang6 March 2011Zaharuddin Abu KassimSyed Ibrahim Syed AhmadDeath (heart attack)TenangJohor30 January 2011Sulaiman TahaMohd Azahar IbrahimDeath (blood infection and diabetes)GalasKelantan4 November 2010Che Hashim Sulaiman PASAb. Aziz YusoffDeath (colon cancer)Pelabuhan KlangSelangorCancelledBadrul Hisham Abdullah BN (UMNO)colspan=3 Declared vacant by the Speaker due to long absence without the leave of the Speaker. However, the Court decided there is no vacancy and SPR did not hold a by-election.Kota SiputehKedahAbu Hasan Sarifcolspan=3 Bagan PinangNegeri Sembilan11 October 2009Azman Mohammad NoorMohd Isa Abdul Samad BN (UMNO)Death (sepsis)Permatang PasirPenang25 August 2009Mohd Hamdan Abdul Rahman PASMohd Salleh Man PASDeath (heart attack)Manek UraiKelantan14 July 2009Ismail YaacobMohd Fauzi Abdullah Death (heart attack)PenantiPenang31 May 2009Mohammad Fairus Khairuddin PKRMansor Othman PKRResignationBukit SelambauKedah7 April 2009Arumugam VengatarakooManikumar SubramaniamResignationBatang AirSarawakDublin Unting Ingkot BN (PRS)Malcom Mussen Lamoh BN (PRS)Death (stroke)BehrangPerakCancelledJamaluddin Mohd Radzi Independentcolspan=3 Declared vacant by the Speaker due to change of party allegiance. However, SPR decided there is no vacancy and did not hold a by-election.(see:2009 Perak constitutional crisis)JelapangHee Yit Foong colspan=3 Changkat JeringMohd Osman Mohd Jailu colspan=3 SanglangPerlisAbdullah Hassan BN (UMNO)Hashim Jasin PASElection declared null and void as wrong winner has been announced. However, SPR did not hold a by-election and hand the seat to correct winner. Source:
2004–08
By-election State Date Incumbent Party Winner Party CauseIjokSelangor28 April 2007Sivalingam Arumugam Karuppiah BN (MIC)Parthiban Karuppiah BN (MIC)Death (heart attack)MachapMalacca12 April 2007Poh Ah Tiam BN (MCA)Lai Meng Chong BN (MCA)Death (renal failure due to lymphatic cancer)Batu TalamPahang28 January 2007Tengku Paris Tengku Razlan BN (UMNO)Abdul Aziz Mat Kiram BN (UMNO)Death (colon cancer)Pengkalan PasirKelantan6 December 2005Wan Abdul Aziz Wan Jaafar PASHanafi MamatDeath (liver cancer)Ba'kelalanSarawak18 September 2004Judson Sakai Tugal BN (SNAP)Nelson Balang Rining BN (SPDP)Death (helicopter crash)Kuala BerangTerengganu28 August 2004Komaruddin Ab. Rahman BN (UMNO)Mohamad Zawawi Ismail BN (UMNO)Death (heart attack)
1999–04
By-election State Assembly Date Incumbent Party Winner Party CauseAnak BukitKedah18 July 2002Fadzil Noor PASAmiruddin Hamzah PASDeath (heart attack)KetariPahang31 March 2002Loke Koon Kam BN (Gerakan)Yum Ah Ha @ Yim Ah Ha BN (Gerakan)Death (jawbone cancer)Indera KayanganPerlis19 January 2002Khor Lian Tee BN (MCA)Oui Ah Lan @ Ng Ah Lan BN (MCA)Death (colon cancer) LikasSabah21 July 2001Yong Teck Lee BN (SAPP)Yong Teck Lee BN (SAPP)Election declared null and voidLunasKedah29 November 2000M Joseph Philomin Joseph Fernandez BN (MIC)Saifuddin Nasution Ismail KeADILanDeath (murder)SanggangPahang1 April 2000Abdullah Kia BN (UMNO)Redzwan Harun BN (UMNO)Death (stroke)
1995–99
By-election State Assembly Date Incumbent Party Winner Party CausePasir TumbohKelantanCancelledDaud Yusuf PAScolspan=3 Death (heart attack)JelawatCancelledMohd Daud Ja'afar S46colspan=3 Death (colon cancer)Sungai BakapPenang8 November 1997Ooi Theng Bok BN (Gerakan)Lai Chew Hock BN (Gerakan)Death (road accident)Changkat JeringPerak8 November 1997Mohamad Razlan Abdul Hamid BN (UMNO)Mat Isa Ismail BN (UMNO)Death (cancer)KidurongSarawak25–26 October 1997Wong Sing Ai DAPMichael Sim Kiam Hui BN (SUPP)Election declared null and voidSemerakKelantan11 August 1997Sulaiman Ahmad PASKamaruddin Mohd Nor BN (UMNO)Death (stroke)MelekekMalacca14 June 1997Mohd Zin Abdul Ghani BN (UMNO)Nawi AhmadDeath (brain stroke due to diabetes)RepahNegeri Sembilan29 May 1997Lay Chun Tai @ Loy Chee Tai BN (MCA)Gan Chin Yap BN (MCA)Death (brain stroke)PermatangSelangor29 May 1997Jamaluddin Adnan BN (UMNO)Abu Hassan Omar BN (UMNO)Resignation (to contest in a Kuala Selangor by-election)KemenaSarawak24–25 May 1997Celestine Ujang Jilan BN (PBB)Celestine Ujang Jilan BN (PBB)Election declared null and voidBukit BegunanSarawak15–16 March 1997Mong Dagang BN (PBDS)Mong Dagang BN (PBDS)Pulai ChondongKelantan6 January 1997Mohamad Noor Ahmad S46Zulkifli Mamat PASDeath (cancer)Bukit AsahanMalacca22 June 1996Arunasalam Narayanan BN (MIC)R. Raghavan BN (MIC)Death (road accident)
1990–95