Driving in Kos gives visitors freedom to reach Kos Town, Kefalos, Tigaki, Marmari, and Zia without relying on schedules, and the island follows the Greek rule of driving on the right-hand side. This guide focuses on the 2026 Greek Road Traffic Code (KOK), the rules that matter at Kos International Airport (KGS / Ippokratis / Hippocrates), and the fines that can affect a rental from Autoway Kos, Geo Rent A Car, or Costas Car Rental. For most visitors from the UK, US, Canada, Australia, Gibraltar, and EU/EEA countries, an International Driving Permit is not legally required on Kos under Law 4850/2021, Article 25 §3, published in FEK A 208 on 05/11/2021. That law recognises valid national licences from those countries, so a driver can legally rent from King of Rent a Car, Trust Kos, or Rentacar-Kos with a national licence only. The law is published in the Government Gazette and reflected in Greek tax-law references such as Taxheaven.gr, which makes it the clearest legal basis for licence checks in 2026. If a licence is issued outside the recognised list or is not printed in the Latin alphabet, an IDP is still required and must be shown with the original licence. Keep a screenshot or PDF of Law 4850/2021 on your phone if an agent at Kos International Airport asks for an IDP despite the law. ⚠️ An IDP is not a replacement for the original licence, and a rental company can still refuse the car if the names do not match the booking. The 2026 KOK reduced the default urban limit to 30 km/h in towns and villages, while rural roads remain 90 km/h and motorway limits remain 130 km/h, although Kos has no motorway network. The Greek Ministry of Digital Governance has been rolling out AI-powered traffic cameras across the South Aegean, and enforcement is relevant on routes around Kos Town, Antimachia, and the airport road to KGS. The strongest practical examples for island drivers are the main corridor between Kos Town and Kos Airport, the approach to Kefalos, and other higher-speed sections where seatbelts and phone use can also be monitored. In many cases, the fine is sent to the rental company first, and agencies such as Eco Rentals, Ilias Rentals, or Exer may then charge an administrative fee of €20-€30 to the card on file. On Kos, treat every built-up road as a 30 km/h zone unless signs clearly show otherwise, because camera enforcement is designed around the KOK update. 💡 If your booking with Avis, Hertz, or Sixt includes GPS tracking or telematics, driving behaviour can also be visible to the fleet team after a violation notice. Greek fines are fixed by offence category, and the KOK links many violations to temporary licence suspension, which is why the exact amount matters for visitors driving between Mandraki, Lambi, Psalidi, and Marmari. The table below summarises the 2026 penalties that are most relevant to rental-car users in Kos and the wider Dodecanese. The table matters for rental customers because companies such as Goldcar, Alma, and Europcar may receive the notice first and then pass the charge to the renter with an added admin fee. The KOK fine structure also makes a strong case for choosing full coverage or FDW where available, because a separate traffic fine does not remove the renter’s duty to pay the authority. Greece applies a low alcohol limit for drivers, and the standard legal threshold is 0.05% BAC or 0.25 milligrams per litre of exhaled air. Novice drivers with less than two years of licence age, motorcyclists, and commercial drivers face a stricter 0.02% BAC limit, so the law can be tighter than visitors expect after dinner in Kos Town or drinks near Kardamena. Police breathalyser checks are common on weekend nights, especially on the roads linking Kos Town, Psalidi, and Tigaki, and the safest rule is not to drive after drinking at all. A small beer can be enough to create risk for an 80 kg adult, so a taxi or prebooked transfer is the safer option after a night out. Insurance from CDW, SCDW, or FDW does not protect a driver from an alcohol offence, and a rental agency can still report the incident even if no crash occurs. Kos Town uses colour-coded parking zones, and the system is the simplest way to avoid an €80 fine while visiting the port, shopping streets, or the beachfront near Lambi and Psalidi. Blue lines mean paid parking, white lines mean free spaces, and yellow lines mean no parking because they are reserved for loading, taxis, or emergency access.