The Teaching Council is reissuing thousands of teachers' practising certificates.
It is replacing annual certificates with documents valid for three years, as a result of a High Court decision last week.
The High Court last week quashed the council's move in February to annual certification.
Thecourt's judgement said the council had not consulted teachers properly on the change and was charging teachers for costs it was not permitted to charge for.
That means the change will reduce the cost of certification to teachers by more than half, creating a shortfall in council income likely to run to millions of dollars.
The court decision said the council had warned it faced insolvency if it was forced to drop its new annual certification system and fees.
The council said it is now working with the Minister of Education and Ministry of Education to ensure it remains financially stable.