It is said that the name of Emperor Uda came from the place where he abdicated (Tsuigo is sometimes considered to be a type of posthumous name, but strictly speaking these are two different names); however, he spent most of the time at Ninna-ji Temple Omuro, Teijino-in and Rokujo-in (though another theory says the reason was that Emperor Uda spent his childhood at Uda-in, which was the house of his father, Emperor Koko, when he was the Imperial Prince).
通説では譲位後の在所の名称より宇多天皇と追号された（追号も諡号の一種とする場合もあるが、厳密には両者は異なる）と言われているが、実際の居宅は仁和寺御室・亭子院・六条院を主としていたという（宇多院は元は父の光孝天皇の親王時代の邸宅で、宇多天皇はここで成長したからだという異説もある）。