The youths have been charged with burglary other than dwelling and remanded to court.
It follows the arrest of fourth youths, after the burglary took place in the early hours of yesterday.
North Wales Police said: “During the early hours of September 6, we responded to a report of a burglary at a local hotel in Llandudno.
“Four youths were arrested in relation to this incident and three have since been charged with burglary other than dwelling and remanded to court.”
Temporary district inspector, Catherine Walker, added: “North Wales Police are committed to robustly dealing with those responsible for causing our local communities harm.
“We welcome the support of local businesses and residents to assist us with our investigations.
“We will be conducting high visibility patrols in Llandudno and would encourage the public to report incidents to us.”