The SDLP spent nearly 10 times as much as Sinn Féin in last year's Assembly elections, according to figures reported by the political parties.
The SDLP - beaten into second place for the nationalist vote for the first time - paid out about £2 per vote received, while Sinn Féin's cost it 18p each.
Campaign expenditure figures issued by the Electoral Commission showed the SDLP as the big spender and also that the Ulster Unionists spent over £20,000 more than the Democratic Unionists and still lost their place as the dominant party among unionism.
It was the first time the parties had to report their election spending. The Commission received these returns from 10 parties on their expenditure:
• SDLP - £234,911.
• UUP - £170,912.
• DUP - £147,867.
• Progressive Unionist Party - £40,041.
• Sinn Féin - £28,765.
• Alliance Party - £24,801.
• Women's Coalition - £8,150.
• UK Independence Party - £5,190.
• Conservative and Unionist Party - nil .
• Northern Ireland Unionist Party - nil.
Mr Séamus Magee, head of the Electoral Commissioner's Northern Ireland office, said:"The publication of this information enables the public to see how much parties spend and how their campaign funds are used to put their message across." - (PA)