I've booked a hotel on Booking.com using an empty debit card. Can the hotel still enforce their no-show/cancellation charge?

I don't quite understand why you're "shocked" at the cancellation fee or why you find it "outrageous"? When you reserve a hotel, you make a promise to show up, and the hotel promises to give you a rate that's cheaper than usual. If you cancel, the hotel gets no money from you and is left scrambling to fill that room, which is why cancellation fees are used to mitigate the damage. If anything, it's not unusual to have fully prepaid rates, meaning that once you've booked, you're charged the entire fee, even if you cancel within 5 minutes.

But in any case, as Burhan says in his answer, since you have no balance on the card, what happens next is mostly up to your bank and you may well get away without paying a cent. But if the bank does decide to charge you, I don't see what grounds you would have to contest the charge, you were almost certainly notified about it (albeit in small print) when you made the original booking: Booking.com promises "no cancellation fee" on "most", but not all, rooms.

Assuming they charge the fee, since you have zero balance the charge won't be successful.

I believe booking.com does not control this, but the individual hotels do. You might want to check with the hotel (and the room/rate combination) you selected.

Some rooms which are discounted are either pre-paid or have a minimum night charge, or a hefty cancellation fee. I think you may have selected such a room+rate combination.

Either way, what happens depends on what kind of card it is and what kind of agreement you have with your bank. You can contact the hotel to contest the charge (although, I am not sure how far that would go to be honest - I have not had much success in this department).

Regarding your booking:

1. They may charge you a minimum night charge if the booking is not cancelled (that is, they have not received the cancellation fee/penalty).

2. They may try to charge the cancellation fee again.

You can also choose to call your bank and refuse the charge.

Always read the fine print. People rush into making a room reservation based solely on the rate or the pictures. When you reserve that room, you are entering into a legally binding contract. You are agreeing to the terms and conditions on that site and for the hotel.

Try contesting the charges in court or with the bank and good luck to you. Whether you think it's fair or not, or whether you like the terms and conditions is irrelevant after the fact. Once you've "confirmed" that you agree by hitting the reserve button And sending the merchant your order you are required to uphold your end of the contract.

Saying you didn't see the information on the website or vendors advertising pages is not a good argument either. The burden of proof is on the accuser. Be prepared to provide proof that the information was not provided BEFORE the purchase was made. Usually the information on reservation pages is right next to the reserve button. Sometimes it is before the checkout page.

My advice is to just stay away from the prepaid reservations since the savings are not nearly all that much lower. 3 party websites like Expedia, booking.com etc, are travel agencies. They will get a fee for sending your reservation to the hotel. If you have an issue at the hotel, you will need to go back to the 3rd party to resolve the billing issue.

Call hotels in the morning hours and ask for a manager (GM) to get answers to your booking questions. Also ask for discounts from the manager rather than the desk staff. Ask about the policy for refunds and anything else you think you should know. Last, take names of the person you spoke to, their positions and get confirmation or cancellation numbers. I can't count how many people don't do this and find out that they've been charged as a no show for a reservation they cancelled, but can't provide a cancellation number or name of the person they spoke to. Other show up with no reservation at a sold out hotel and having no confirmation number means you have no grounds for recovery.