Water Safety New Zealand says making skipper licences compulsory might prevent some boat accidents, but financially it is not realistic.
The comment follows the deaths of So'saia Paasi, 45, and his seven-year-old son Tino who were swept away on Sunday after their dinghy capsized near the Mangere Bridge in South Auckland.
At present, controlling a boat does not require a licence.
Water Safety NZ chief executive Matt Claridge says it would make a difference if licences were mandatory, but this would be too costly.
Mr Claridge says greater emphasis needs to be placed on education.