Each holiday season, the order-by date shows on every product page and in your cart: about two weeks before Christmas for the US, and about a week earlier outside the US.
We can't guarantee arrival, because some things are outside our control, like weather and carrier delays. But every year we do all we can to help Santa get your gifts there on time. If anything goes wrong, we're here with other ideas, like an e-gift card that arrives by email in minutes. We know how much a gift means.