Absolutely. You could include that information on the invitation or on a separate enclosure. If it is included on the invitation, please follow the same formality used in the rest of the message adding "reception to begin at 5 pm, destination title, The favor of a reply is requested, address. If it is included as a separate enclosure or invitation, it would read similarly to the wedding invitation only stating that the reception will held on date, time, location title, favor (or favour if it is formal), of a reply is requested, address.
Congratulations on your upcoming wedding. Rebecca Black, Etiquette Now
In case you were wondering if it was appropriate to plan your reception to be held three hours after your wedding, yes. It is always better to have your reception soon after the wedding, but many times it is impossible.
It would be considerate to have some sort of activity or a room with refreshments set up in a near-by hotel for your out-of-town guests so they may wait comfortably. Rebecca Black, Etiquette Now
Wedding at 2pm, dinner buffet reception when?
