Many GRE students are still confused about sending their official GRE score reports to prospective universities. You can send up to four official scorecards for free. You have to send these score reports on the day of the GRE test. The institutions where you send your GRE scores will not know the other places where you will be submitting your reports.
If you submit your scores after your test day, you will have to pay an additional fee per university. This amount will become excessive in case you are applying to tens of places.
Therefore my suggestion is to at least get those four score reports on the test day.
Moreover, many GRE aspirants ask whether they need to memorize the shortcodes of prospective universities. You do not need to since the computer you take your actual GRE test will provide you with a drop-down menu of all the schools around the world. You can then choose the institutes where you want to send your GRE score report. In case you have taken the GRE test multiple times, you will have the option to select which score you want to send to a particular school.
Once you send your official scores, you cannot cancel them. As soon as you’ve finished the test, you will have a few minutes to decide if you want to cancel your scores. Once canceled they cannot be retrieved.