Espresso Embassy has great vibes with perfect espresso. You get fast Wi-Fi signals and power outlets all over the place.
Cirkusz is one of the best place to work from with super fast internet up to 105mbps. It cost around 6$ a day.
Telenor- offers very good service with nice plans. The staff is great too.
They have daily passes at 10 euros, also with 5/10 day options. They have meeting rooms and lots of community events that makes this place my favorite. Kaptar is another nice coworking space to check out.
Best tip about Budapest: Digital Wombats. It is a group for Nomads. We meet, share experiences, learn and enjoy.
Impact Hub Budapest - One of the best coworking space in Budapest! Very spacious with natural light, awesome community, great events, central location.