I'm a non-EU passport holder. If I wanted to travel to B/H does it mean I have to apply for another visa or would my Croatian visa be allowed to go inside B/H? Thanks very much.
First, there are dozens of non-EU countries whose citizens can enter Bosnia without a visa. If you are a citizen of one of those countries, you can enter with or without your Croatian visa:
LIST OF COUNTRIES THAT ARE NOT REQUIRED BOSNIA-HERZEGOVINA ENTRY VISA
Albania, Andorra, Antigua-Barbuda, Argentina, Australia, Austria, Azerbaijan, Bahamas, Bahrain, Barbados, Belgium, Brazil, Brunei, Bulgaria, Montenegro, Czech Republic, Chile, Denmark, Dominica, Estonia, Finland, France, Greece, Grenada, Georgia, Guatemala, Holland, Honduras, Croatia, Ireland, Iceland, East Timor, Italy, Israel, Japan, Canada, Qatar, Cyprus, Kiribati, Colombia, Korea - Republic, Costa Rica, Kuwait, Latvia, Lichtenstein, Lithuania, Luxembourg, Hungary, Macedonia, Malaysia, Malta, Military Order of Malta, Marshall Islands, Mauritius, Mexico, Micronesia, Monaco, Moldova, Nicaragua, New Zealand, Norway, Germany, Oman, Palau, Panama, Paraguay, Peru, Poland, Portugal, Romania, Russia*, Salvador, Samoa, San Marino, Seychelles, Singapore, United States of America, Slovakia, Slovenia, Solomon Islands, Serbia, Saint Lucia, Holy See, St. Christopher and Nevis, St. Vincent and the Grenadines, Spain, Sweden, Switzerland, Tonga, Trinidad and Tobago, Turkey, Tuvalu, UK of Great Britain and North Ireland, Ukraine**, United Arab Emirates, Uruguay, Vanuatu, Venezuela.
*up to 30 days during a period of 60 days starting from the first day of entry, **up to 30 days in two months from the first day of entry
Second, if you are not a citizen of one of those countries, you may be able to enter for up to 30 days with your Croatian visa, if it is a multiple-entry visa and its validity is sufficient, because Croatia is a European Union member state:
Citizens of countries with which BiH has a visa regime can stay up to 30 days in Bosnia and Herzegovina without visa under condition that they posses a valid multiple visa or residence permit issued by the Schengen Agreement country, European Union Member States or United States of America. Such visas or resident permits should be valid for at least 30 days longer than the date of entry into our country.