They are among 10 main protagonists from the hit HBO fantasy programme, based on the books by George RR Martin, who feature in the set that goes on sale on January 23.
As well as the characters played by Emilia Clarke, Kit Harington and Maisie Williams, the roll-call of characters from Westeros also includes Cersei Lannister (Lena Headey), Sansa Stark (Sophie Turner), Tywin Lannister (Charles Dance), Eddard Stark (Sean Bean), Olenna Tyrell (Dame Diana Rigg), Tyrion Lannister (Peter Dinklage), and Jaime Lannister (Nikolaj Coster-Waldau).
There is also a five-stamp sheet featuring images of the Night King and his undead White Walkers, giants, direwolves and dragons, and the Iron Throne.
The collection's release comes ahead of the eighth and final series, which is currently in production.
Fans can pre-order stamps now from the Royal Mail website and buy them from January 23 at Post Office branches across the UK or by calling Royal Mail's customer service line.