Most public beach sunbeds in Montenegro work on a walk-up, first-come-first-served basis — there is no central booking system. You simply arrive, find an available lounger, and pay the attendant on the spot. This is the norm at popular spots like Slovenska Plaza in Budva, Petrovac, and Sutomore.
For organised beach bars and clubs, especially those with premium daybeds or canopy baldahins, reservations are usually possible and recommended in July and August. Contact them directly by phone, WhatsApp, or Instagram DM — most bars list a number on their social media profile. Expect to confirm with your name and arrival time, and sometimes a minimum spend rather than a fixed fee.