Depending on the relationship with the person retiring, would determine what to say in a written Happy Retirement. If the relationship is not a close on, a simple "Congratulations and Happy Retirement" would be sufficient.
"Maligayang pagreretiro" is how you say happy retirement in Tagalog.
Happy retirement! translates as Alles Gute für den Ruhestand.
If you want to say happy retirement in Italian you would say, pensione felice. You would say good luck by saying buona fortuna.
"Feliz aposentadoria."
In Afrikaans, you can say "gelukkige aftrede" to wish someone a happy retirement.
Feliz jubilación! or simply "Felicidades!"
In finnish: hyvää eläkettä
Irving Salomon has written: 'Retire and be happy' -- subject(s): Retirement
You can say "Soy maestro jubilado", or "Soy maestra jubilada" for a female.
You can say "joyeuse retraite" in French to wish someone a happy retirement.
Happy journey : Rehla sae'eda written as : رحلة سعيدة
Deseo que tengas un jubilación feliz.