Do United Kingdom passport holders need a visa to visit RS?

No visa required. UK ordinary passport holders can enter Serbia visa-free for up to 90 days within any 180-day period for tourism or business. British citizens holding an ordinary passport do not need a visa to visit Serbia for short stays. Entry is permitted for up to 90 days within any 180-day (6-month) period for tourism or business. Serbia is NOT part of the Schengen Area and is not an EU member, so the Schengen 90/180 rule and the EU ETIAS scheme do not apply to a trip to Serbia (your Serbian days are counted separately from any Schengen days). No advance application, online form, or fee is required for the visa-free entry itself. Travelers must hold a passport valid for at least 90 days beyond their planned departure from Serbia. A key local rule: all foreign visitors must register their address with the local police within 24 hours of arrival; hotels and registered accommodation do this automatically, but those staying in private homes or unregistered lodgings must register themselves at the nearest police station to avoid fines. Always ensure your passport receives an entry stamp at the border, as leaving without one can cause serious problems on exit. Stays beyond 90 days require a temporary residence permit or appropriate long-stay visa arranged via the Serbian authorities/embassy.