Competitive pressure is pushing banks to cut the cost of sending money overseas.

Mainstream banks have been criticised for the cost of international money transfers - which have ranged from $15 to $25 when the payment is made by internet banking. It is usually more expensive to make the transfer in the branch.

But new operators, and cryptocurrencies, are starting to force change.

ANZ this week announced its goMoney app would allow people to send money internationally from their phones for a transfer fee of $9.

It is also offering a reduced fee to send money to Pacific Islands. It now costs $7, reduced from $18, to send money to the Cook Islands, Fiji, Kiribati, Samoa, Solomon Islands, Tonga and Vanuatu via goMoney or internet banking.

TransferWise entered the New Zealand market in May, charging about 0.7 per cent of the amount converted. Another, KlickEx, can be used to send money from New Zealand to Fiji, Samoa and Tonga and charges $3.

Banking expert Claire Matthews, from Massey University, said it was becoming more common to send money overseas, and it did not make sense to pay big charges, especially on small amounts. "If the others haven't moved yet, they will."

Matthews said cryptocurrencies increasingly become another option, particularly when people needed to get money to recipients who did not have a bank account.

But Alex Sims, the University of Auckland's head of department of commercial law, who researches regulation of cryptocurrencies, said it was unlikely that would be done with Bitcoin, because of the high transaction fees.

IBM is working with KlickEx to trial using cryptocurrency Stellar Lumens when making payments to the South Pacific.

"Their trial shows that it is a question of when and not if cryptocurrencies will be used to send money overseas."

How much is the transfer fee to send $1000 to Australia?

Western Union: $10 to a bank account, $25 to cash

Westpac: $20 (online)

ANZ goMoney: $9

​KlickEx: $3

TransferWise: $6.95 (from a bank account)