"If somebody comes in acutely, then we have to treat them, and sometimes that comes up to $10,000 or $20,000 and sometimes that can't be recovered," Dr Chamberlain said.
Every other district health board in New Zealand faced the same issue, he said.
The NDHB was unable to say how old the debts were, except that they had been outstanding for more than six months.
The debt from those patients was from acute conditions, though some patients who presented with injuries may be covered by ACC even if they were from overseas.
Board member Greg Gent said while it was doubtful the debts would be repaid, it was not the end of the matter.
"There isn't reasonable expectation that this is going to come but that doesn't mean that we aren't going to keep trying," he said.
All debts over $50 had been referred to the DHB's debt collection agency and overseas visitors with debts of more than $1000 had their debts lodged with Immigration New Zealand.
The submission to the board stated: "All avenues have been exhausted trying to recover these debts."
Over the two-week summer holiday period, 3 per cent of admissions to the Whangarei Emergency Department, or 59 patients, lived overseas.