Legislation giving workers Monday off should Waitangi Day or ANZAC Day fall on a weekend has passed its first reading in Parliament.
The private member's bill in the name of Labour MP David Clark passed by 61 votes to 60, with the deciding vote of United Future leader Peter Dunne.
Labour's deputy leader Grant Robertson, who originally drafted the bill, says employers know that having rested workers is better for productivity.
He says the National Party has never liked the idea of workers getting holidays, which is why it voted against it.
It will now be considered by the Transport and Industrial Relations Select Committee.