Men: every 90 days. Women: every 120 days. That’s the national standard, and it exists because your body needs that time to fully replace its iron stores.
On our register this is automatic: after you tap “I donated today”, you’re hidden from matching until your interval clears, then brought back. You will never be asked too early.
Regular donors — two to three times a year — are the quiet backbone of any state’s blood supply. One person, donating twice a year for a decade, contributes 20+ units. That’s up to 60 patients helped, after component separation.
Related: what to eat before donating · what to do after