Yes, in 2026, your Suica card is fully usable in Kyoto. Thanks to the "National Interoperability" system established years ago, major IC cards like Suica, PASMO, and ICOCA are interchangeable. You can use your Suica (including the digital version on your iPhone or Android) to pay for fares on the Kyoto City Subway, JR West trains, and nearly all local Kyoto city buses. You can also use it at convenience stores and many vending machines throughout the city. A supportive peer warning: while you can use it there, you generally cannot get a refund for a Suica card in Kyoto, nor can you easily resolve technical errors (like a "missed tap") at a non-JR East station. If your Suica malfunctions in Kyoto, you may have to wait until you return to a JR East area (like Tokyo or Sendai) to fix it. For 2026 travelers, it's the most convenient way to travel between Tokyo and Kyoto without constantly buying paper tickets.