Schengen member states require Schengen visa. Non-Schengen EU member states which have signed the Schengen acquis allow permanent residence permit holders in Schengen members to visit them for up to 90 days without requiring a visa. The UK is not a Schengen member, but is an EU member. Does a non-EU citizen with a permanent UK residence need a visa to visit the other EU non-Schengen states?
Beside the UK, there are five other non-Schengen EU states:
Ireland, like the UK and to maintain their “common travel area”, opted out of the Schengen area and will not join in the foreseeable future. The common travel area mostly applies to UK and Irish citizens, it does not entail a mutual recognition of all visas and residence permits. Non-EU citizens who hold a UK residence permit might therefore still require a separate Irish visa to visit Ireland (there are some exceptions, detailed on citizensinformation.ie).
Romania, Bulgaria and Croatia are supposed to join the Schengen area soon (formally, Cyprus should too but it needs to resolve its long-standing conflict with the Turkish-controlled area first and that might take even longer). Because of this, they all apply Regulation (EC) No 539/2001 which means they have the same visa requirements as Schengen member states (also known as “states that fully apply the Schengen acquis”).
Croatia said it strives to apply to join in the coming year or so. Bulgaria and Romania are ready to join according to the Commission's evaluation and were supposed to do it at the beginning of 2014 but their status is now in a limbo because several older member states blocked the final step.
Following this, the EU took a decision that allowed these countries to implement rules modeled after those of the Schengen area without actually joining it (so that they now basically recognize Schengen visas but still cannot issue them or lift border checks). In practice, this means they recognize visas and residence permits from Schengen member states and from each other but not those issued by the UK or Ireland, just like current Schengen member states.
Other relevant links:
- Romanian Ministry of Foreign Affairs
- Croatian Ministry of Foreign and European Affairs
- Bulgarian Ministry of Foreign Affairs