Ferry to Ibiza - do I need to book or can I just turn up?



Gonna get the ferry from Ibiza to Barcelona tomorrow at 23.59 getting to Ibiza at 08.00 (It´s a Transmediterranea). Do I need to book in advance or can I just turn up and will be able to get on?

If I need to book, does someone have a number for them?

Thank you, total Ibiza virgin here, was meant to be going down to Fuengirola for the AV festival but totally impossible to get a train so gonna head to Ibiza instead.

arse, just found out the trasmediterranea is fully booked

ben trying to call Umafisa but all I get is an answermachine message that I don´t understand. CAn someone help, please.
have you spelt that correctly, I´m not getting any hits on Google for it.

Baleria or Balearia not sure! they sail from Ibiza daily to Denia but not sure about Barcelona. Sorry im not much help!
Umafisa Lines are booked through Trasmediterranea (or they were when we took it)... so it may be useless to try to get ahold of Umafisa anyway. Have you checked into flights? If there are any -- I'd definitely recommend that over the ferry.