Tourism Dunedin chief executive Hamish Saxton said he had heard from hotels and motels about the attempted overseas email scam and is warning people to be vigilant.
As part of the ruse, scammers book several rooms with accommodation providers, or in some cases to transfer flight deposits, using a credit card.
They contact the accommodation providers later to cancel the booking, and then transfer the deposit, which usually has not cleared, into a different bank account.
The credit cards used were often obtained fraudulently and the scammers were attempting to launder the money through a third party, he said.
The amounts ranged up to $US6000 ($NZ8100) and business owners should treat such emails with caution, he said.
Otago Motel Association president Neville Butcher said these type of scams were "fairly consistent" in the industry, and cautioned moteliers to be vigilant.
One rule when dealing with credit cards was to refund money on the same card rather than any other account.
Mr Butcher said while he was not aware of any motelier losing money in the scam, victims were unlikely to publicise their loss.
A Consumer Affairs spokeswoman said the ministry was aware of the scam, and businesses should be suspicious when asked to refund through a method different to the payment.
To avoid overpayments or refund scams, businesses should make deposits refundable, ask for deposits to be made by money transfer, and not accept extra payments.
Earlier this month, the University of Otago issued a warning about a foreign scam aimed at students looking for flatmates.
