If you made your cert dives on the weekend, and filled out your portion of the PIC, and supplied the instructor with a picture, PADI....2 weeks + a week. It all depends on how many OW certifications are being processed at the time. If for some strange reason you don't have your C-card in 4 weeks, go back to your instructor because something is wrong. Your instructor can go to PADI online and see if your PIC has been processed and he can check with PADI to see when your C-Card was mailed. I've only had one student that didn't receive a C-Card in under 3 weeks, usually 2 weeks. This student was in the 3 month timeframe, I checked and the PIC was processed, so I called PADI and they overnighted the C-Card to the student.