I accidentally ordered something that is on pending list and I want it cancelled but I can't. Do I still need to pay for it when it arrives at my house?

I really need to cancel it. Would I be in trouble?

No idea what company you ordered from. This is not a customer service company for any mail order firm. We are an international question and answer site.

My first impression, is that you refuse delivery of item. But you may owe shipping or restocking charges, it will depend on the terms of the order