Cres and Losinj are not the easiest islands to reach but well worth the trouble when you get there. The two islands located in the Gulf of Kvarner are practically joined and are connected by a small bridge at the town of Osor. So if you take a ferry to one island you can reach the other.
The car ferry from Brestova on the mainland to Porozina on the island of Cres is a 20 minute crossing and in the summer there are 11 crossings a day from 5.30am till after midnight. Line 334 with Jadrolinija. But note that from Porozina to Mali Losinj is 80 km and will take at least one hour 20 minutes by car.
Another option is to drive to Krk island which is connected to the mainland by bridge and take the car ferry (Jadrolinija line 332) from Krk island to Merag on Cres. A 25 minute crossing that runs regularly with 13 crossings a day in the summer.
There is a fast foot passenger catamaran from Rijeka to Mali Losinj. It is essential to check the time table (Jadrolinija line 9308) as it stops and various places along the route and the journey time can range from three hours to four hours 50 minutes depending on the number of stops and that varies with the day of the week.
Ferry company Catamaran Line provide a foot passenger service connecting Pula in Istria with Zadar in Northern Dalmatia (line 9141). The route stops at Mali Losinj in both directions. Ferries run five days a week in the summer leaving Pula at 7.00am and Zadar at 16.00. The journey time to Mali Losinj is 3 hours 15 minutes from Pula and two hours 45 minutes from Zadar. Check the time table on the Catamaran Line website