Mail-in sweepstakes offer a free alternate method of entry (AMOE) that lets you enter without making a purchase. By U.S. law, any sweepstakes tied to a product purchase must provide a free entry option — and mail-in is the most common. These entries carry the exact same odds as purchase entries. Many experienced sweepers focus on mail-in sweepstakes because fewer people bother with the extra step, which can mean better odds.