The Shamrock Irish Bar will satisfy your needs. Always crowded also during weekdays, mostly expats. It's located somewhere you can go to experience the city's nightlife, even during weekdays when other bars and clubs might be less crowded.
3 recommendations in Nightlife
Recommendations in Warsaw
Located in the city center, Kufle i Kapsle is a cozy craft beer pub with good taps, fast service, and a charming old interior. It's a great spot to grab a drink and relax with friends.
Hydrozagadka is a nightclub that hosts theme nights, including an 80s, 90s, and 00s night, which might attract an older crowd. It's located somewhere in Warsaw, and you can find it by asking locals or looking up its address.