Spilled is favoured in American English as both the past tense and past participle. British English, as you may have suspected, prefers spilt, also for both.
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▷ Spilt or Spilled – what is correct and how to use it - Blog EN
▷ Spilt or Spilled – what is correct and how to use it - Blog EN
Word Choice
New Zealand English: burned vs burnt - Clearlingo Editing and
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▷ Spilt or Spilled – what is correct and how to use it - Blog EN
spill meaning of spill in Longman Dictionary of Contemporary
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