Flying into Zagreb for eight nights in early April. I would like to drive to Ljubljana Slovenia and I am not sure what car rental company will allow cross border crossings with out a large fee. I have not seen much information on the rental car websites. Thanks!

Probably it's not a big deal to be able to drive to Slovenia from Croatia in a rental car, as long as you return the car back IN Croatia again. You do need to have the right papers, though.

Have you considered taking the train to Ljubljana and simply renting a car there then returning to Zagreb by train? Or do you have stops in between?

I was thinking about a stop at Lake Bled while in the area.
We were going to drive to the coast of Croatia from Ljubljana and work our way back to Zagreb.
I like the freedom of a car to stop in small villages as we are driving the coast.

No problem or extra charges, when going to Slovenia with most rentals. Let them know in advance of your plans.

Check with AutoEurope www.autoeurope.com. If the website doesn't answer your question, call them. I don't think there will be a problem.

Thanks!

I believe Europcar used to have a daily surcharge for taking the car out of Croatia - I've just called up holiday autos and their suppliers allow the cars into slovenia at no charge

Plastic,
Thanks, I read on an old blog that some rental company charged 200 euros to cross into Slovenia. That is what peaked my interest for this question.

I don't know what crossing is like now, but 3 yrs. ago we drove from Trieste, Italy into Slovenia for a few days and then into Croatia. We returned the car in Trieste. We were never stopped crossing into any of the countries. I really think there wasn't even anyone in the booths crossing from Slovenia to Croatia. My point is as long as you return the car where you rented it and you have prior approval, the travel is easy.