In a message to customers posted on its website, the firm’s directors said it was a "heartbreaking decision" brought on by the pandemic.
FRP Advisory Trading Limited will oversee the liquidation of the south coast agency, which was a member of the Advantage Travel Partnership and Abta.
"It is with deep regret the directors of Travelplanners Southsea Limited, after 45 years of trading as Travelplanners, have taken the heartbreaking decision to cease trading and go into liquidation," read the message.
"This is entirely due to the effects of the global pandemic which has decimated the travel industry over the past two years.
