The cruise company parted ways with TBWA\London after just six months.
Hometown landed the business without a pitch. The agency will now be responsible for all Royal Caribbean’s brand and creative work, incorporating TV, digital, press and experiential activity.
Royal Caribbean has briefed Hometown to create a campaign to launch in 2016 that will "shake up" the cruise category.
Mullen Lowe won Royal Caribbean’s global ad business in May after a pitch.
Tamara Strauss, the director of marketing and PR for UK and Ireland at Royal Caribbean, said: "It’s an exciting time for new agencies to come on board as we have ambitious plans. Hometown has great experience in the sector, as well as the challenger mentality we were looking for."
TBWA\London picked up the advertising account in April after a pitch handled by Creativebrief but has since split with the brand.
Richard Stainer, the chief executive at TBWA\London, said: "We had great chemistry with RCI in a pitch earlier this year. They professed a desire to really disrupt the cruise industry, and our strategy absolutely delivered on that.
"Unfortunately, their marketing personnel changed – as did their conviction for the disruptive approach we strongly advocated. We weren't right for them, and they weren't right for us.
"We wish the new team every success moving forward – and we're 'open for bookings' for a cruise line looking for a genuinely fresh approach."