W ASHINGTON—Centrist Sen. Thom Tillis (R., N.C.) said he won’t seek re-election in 2026, less than 24 hours after he voted against a motion to advance President Trump’s tax and spending megabill, drawing public backlash from the president.

Republican Sen. Thom Tillis of North Carolina announced Sunday he is not seeking reelection next year, a day after he was one of only two Republicans who voted against advancing President Donald Trump’s sweeping agenda bill.

Republican Sen. Thom Tillis of North Carolina said Sunday he will not seek reelection next year, an abrupt announcement that came one day after he staked out his opposition to President Donald Trump’s tax breaks and spending cuts package because of its reductions to health care programs.