20 Ways To Say Happy Birthday In Japanese – Full Guide 2025 1 遅くなったけど、お誕生日おめでとう(おそくなったけど、おたんじょうびおめでとう)— osoku natta kedo, otanjōbi omedetō Meaning: “Sorry I’m late, happy birthday ” A polite yet casual way to acknowledge that you’re sending your wishes a bit late Works well for friends and colleagues alike