Wa `alaykum As-Salamu wa Rahmatullahi wa Barakatuh.
In the Name of Allah, Most Gracious, Most Merciful.
All praise and thanks are due to Allah, and peace and blessings be upon His Messenger.
Dear questioner, we would like to thank you for the great confidence you place in us, and we implore Allah Almighty to help us serve His cause and render our work for His Sake.
Answering the question in point, Dr. Muzammil H. Siddiqi, former President of the Islamic Society of North America, states:
"There are different types of sweepstakes. Not all of them come in the category of lottery or gambling. If a sweepstakes is merely promotional where no purchase is necessary, then it is like a prize or award that the business volunteers to advertise its products and to attract more customers. Such sweepstakes are permissible in Islam. But if a sweepstake requires to purchase a ticket or something similar, and get nothing in return for the value except for those who win, then it would be Haram, because that would be gambling.
All kinds of gambling (al-maysir or al-qimar) are Haram in Islam. Allah says, "They ask you concerning wine and gambling. Say (O Prophet), 'In them is great sin and some benefit for human beings, but the sin is greater than the benefitů" (al-Baqarah: 219) Lotteries are, perhaps, the most widespread form of gambling. In most lotteries, the gamblers buy numbered tickets. In many State lotteries in America the chances of winning are one to fourteen million times. Some people have rightly called lottery the most senseless and speculative "investment" on earth. It is deceitful. It lives and thrives by consuming the hard-earned resources of losers. It depends on the losses of many. It robs so many to pay so few. It exploits the weak and seeks to weaken the strong."
You can also read:
Islam Prohibits Gambling