If it's a normal holiday contract and since you are within 12 weeks of departure your deposit will be lost. Depending on the contract you may also be liable for further costs. A holiday that I have currently booked has a sliding scale from 83 days to departure date. In your case you are only 27 days from departure and if your holiday was subject to the same conditions you would be liable for 90% of the total cost. That said, my balance is due twelve weeks before departure and if I don't settle in full the holiday will be cancelled at that point (with loss of deposit). You need to read your holiday's Ts&Cs.