Tamil Nadu's 17th Assembly has five vacant seats following the swearing-in of CM C. Joseph Vijay's government. The seats will require by-elections — and all five will be closely watched as the first electoral test for the new TVK administration.
- AC #141 — Tiruchirappalli East: C. Joseph Vijay (TVK) — vacated May 9, 2026 (chose Perambur as official constituency)
- AC #35 — Maduranthakam: Maragatham Kumaravel (AIADMK) — resigned May 25, 2026; joined TVK
- AC #225 — Ambasamudram: E. Subaya (AIADMK) — resigned May 26, 2026; joined TVK
- AC #101 — Dharapuram: P. Sathyabama (AIADMK) — resigned; joined TVK
- AC #103 — Perundurai: S. Jayakumar (AIADMK) — resigned; joined TVK
Trichy East — The Most Watched Contest
The Tiruchirappalli East by-election is the most politically significant of the five. CM Vijay won the seat in April 2026 with a margin of 27,416 votes over DMK's Inigo S. Irudayaraj (TVK: 91,381 votes, 50.07% vs DMK: 63,965, 35.05%). Having vacated it upon becoming Chief Minister, Vijay used his June 1 Trichy rally to urge voters to support the TVK candidate in the upcoming contest, making it a personal appeal.
AIADMK's Continuing Collapse
The four AIADMK resignations — all following the pattern of joining TVK — reduce the principal opposition party's strength from 47 to 43 in the Assembly. The resignations at Maduranthakam, Ambasamudram, Dharapuram, and Perundurai follow a political realignment that has significantly weakened AIADMK's post-election position under Edappadi K. Palaniswami's leadership.
Impact on Assembly Numbers
With 5 seats now vacant, the effective Assembly strength has dropped from 234 to 229. The new majority mark stands at 115. TVK's coalition commands 144 votes — giving a comfortable working majority. If TVK wins all 5 by-elections, its strength rises to 112, with the coalition exceeding 149 votes total.
Expected Timeline
The Election Commission of India is expected to announce by-election dates by July 2026 at the latest. Political observers expect the contests to be held alongside or slightly after the Tamil Nadu Budget session. TVK, buoyed by its CM's popularity, is favoured in all 5 constituencies — particularly Trichy East where the CM's personal mandate and first-rally speech will be a dominant campaign factor.