|First seen||"The Laws of Gods and Men"|
|Allegiance||Iron Bank of Braavos|
|Portrayed by||Mark Gatiss|
- "Across the Narrow Sea your books are filled with words like 'usurper' and 'madman' and 'blood right'. Here our books are filled with numbers. I prefer the stories they tell. More plain. Less... open to interpretation."
- ―Tycho Nestoris to Stannis Baratheon
Shortly after Tommen Baratheon's coronation, Tycho and two of his colleagues receive Stannis Baratheon and his Hand, Ser Davos Seaworth, who ask them to fund their continuing campaign in Westeros. Tycho points out their weak position and is ready to dismiss them when Ser Davos speaks up, relating how he came into Stannis' service, how the latter is a just man who keeps his word, and how he is the best chance for the Iron Bank to get its money back upon the chaos that would follow the death of the elderly Tywin Lannister. This seems to convince the banker and his colleagues, as they agree to fund Stannis.
|Season Four appearances|
|Two Swords||The Lion and the Rose||Breaker of Chains||Oathkeeper||First of His Name|
|The Laws of Gods and Men||Mockingbird||The Mountain and the Viper||The Watchers on the Wall||The Children|
In the books
In the A Song of Ice and Fire novels, Tycho Nestoris is described as a tall, stick of a man with long legs. He has a gaunt face with a thin rope of a beard growing from his chin which hangs down to his waist. He wears expensive robes of a sober dark purple color, trimmed with ermine fur. He is not introduced until the fifth novel, A Dance with Dragons.
Stannis does not personally travel to Braavos to meet with Tycho: in the early novels the banks' communications with alternatively Stannis or the Lannisters are handled through written correspondence. The TV producers, however, stated that they thought it was important to physically introduce Tycho earlier instead of later. One of Bryan Cogman's initial ideas for "The Laws of Gods and Men" was to have Tycho come to Dragonstone to treat with Stannis, not the other way around: this was also changed to have Stannis visit Braavos, because they realized it was also important to physically introduce the city of Braavos and the Iron Bank itself as soon as possible. Cogman also felt that it made more dramatic sense for Stannis to have to come to Braavos to essentially beg for money, because at the moment he is losing the war, so logically the Iron Bank doesn't think he is significant enough anymore to go through the bother of sending an envoy to meet with him in person. As a result, Tycho's scenes in Season 4 have no direct counterpart in the third novel, though they are a condensation of running subplots involving the Iron Bank which are discussed at council meetings.