By car: there are two routes to choose between when you go from Omis to Split. The first route is the coastal road and the second route is a local road which goes via Gata and Tugare, little villages in the hinterland of Omis. It is recommendable to take this route in the season to avoid traffic jams on the coastal road which are very frequent. After you pass the bridge in Omis turn right and just follow the directions to Split. The travel distance is 29 km which equals a travel time of 37 minutes. However, in general, the coastal road is the faster route. The travel distance is 25.2 km and the travel time is approximately 28 minutes.
By bus: there are several bus travel options from Omis to Split. Firstly, there are travel buses which only pass by Omis on their way to Split and further north. They have few or no stops at all between Omis and Split. You can see the schedule here. Secondly, there is a regional bus number 60 which is very frequent. The schedule for the line 60 can be viewed here. Thirdly, several minivans which drive between Omis and Split; they do not have an official schedule but they have a sign saying Omis or Split - Omis.
Tips on visiting Omis and Split
Both Omis and Split are old cities, so there is plenty to see and to do as well. Regarding sights, Omis has a lot of old churches and a couple of fortresses. For sports enthusiasts, there are many activities, but the most famous is rafting on the Cetina river. For those who want a more peaceful vacation, along the Riviera of Omis you will find many smaller places with beautiful sandy and pebbly beaches; some of them are Duce, Lokva Rogoznica, Pisak... As for Split, the whole old town is a historical site, so it is definitely worth paying a visit.
Please feel free to leave a comment if you have any question in relation to travelling from Omis to Split or vice versa.