A split jackpot occurs when at least two eligible plays match the single combination selected by a draw. The underlying math is a collision problem: duplicate combinations must exist among submitted plays, and the draw must land on one of them.
The revised UK Lotto format began on June 7, 2026, giving every £2 line entry into two rounds in the same draw. Here is how the new rules affect entry mechanics, odds, prizes, claims and UK lottery winnings tax.