Three overseas tourists were arrested and charged within 24 hours after ski staff noticed the passes had been altered.
Sergeant Brian Cameron, of Queenstown, said police were called on each occasion and the three tourists, two from Australia and one from England, are all facing charges of altering a document, which carries a maximum penalty of 10 years imprisonment.
The tourists had their season passes, worth $949 revoked and had been issued a trespass notice by NZSki banning them from Coronet Peak, Remarkables and Mt Hutt skifields for two years.
"The conditions of use for the passes are very clear and made available to everyone who purchases them. Fraudulent use will not be tolerated and, as the penalty demonstrates, this is viewed as a serious offence," he said.
Giving your pass to a friend or relative to use was also an offence.
"If you intend to use the services on offer, ensure you have paid for them or suffer the consequences," he said.
NZSki chief executive James Coddington said people had been trying to manually add a "T" on to their season pass to obtain free transport on the company's buses.
"They are very easily detected. We've caught five people this year so far and they have been processed as usual for fraud. They are referred to police and issued a two-year trespass notice," he said.
Three of the five were caught this week, he said.
"The bus to Remarkables is $5 return, so to lose your season pass for $5 is a bit stupid," he said.
It costs $200 to have a "T" on a season pass, which entitled the bearer to unlimited transport to and from the mountain.
The company could also issue lifetime bans to people fraudulently using other people's season passes.
"We can pick them up when they go through the gates. Every pass has a photo loaded on to it and it is easy to see the person does not match the photo," he said.
