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This is generally not possible, as visas for the CTA are not valid for both countries :
You cannot travel to Northern Ireland using an Irish visa, except if travelling under the British Irish Visa Scheme (explained above). You need a visaΒ issued by the United Kingdom.
If you travel from the Republic of Ireland to Northern Ireland and then wish to return to the Republic, you must have a Multiple Entry visa (explained below).
If you are a Chinese or Indian citizen living in your respective country then the situation may be different, but for most nationalities you need a visa for both countries.
Upvote:3
No, with the default Irish Visit (Tourist) Visa you cannot enter the United Kingdom (including Northern Ireland).
Only with a visa issued against the British Irish Visa Scheme or a combination of Irish and UK Visitor visa is traveling between the Irish Republic and the United Kingdom possible.
Note:
The Common Travel Area rules apply mainly to Irish and British Citizens
During your stay in Ireland
Travel to Northern Ireland & United Kingdom You cannot travel to Northern Ireland using an Irish visa, except if travelling under the British Irish Visa Scheme (explained above). You need a visa issued by the United Kingdom.If you travel from the Republic of Ireland to Northern Ireland and then wish to return to the Republic, you must have a Multiple Entry visa (explained below).
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