When you return the chips it is called "cashing out". The casino doesn't let you buy in with a duffle bag of $250,000 and cash out for a cheque from the casino for $250,000 in the same transaction. You have to go play a low variance game like Baccarat and play your money through like 200%. Then you cash out $240,000 and get a cheque from the casino that you can easily deposit into a Canadian bank. Gambling winnings in Canada are also tax free.