The Steam Packet company says customers who still want to use cash at its ports may be able to do so if they give a week's notice.
Yesterday, the company announced it was going cashless at its land-based facilities to deter crime - although cash will still be accepted on board vessels.
But in a further statement, it now says it doesn't want to penalise travellers who don't have bank accounts.
It says anyone who can't use banking services can discuss alternative payment methods if they contact the company at least seven days before travelling.
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