How many personal statements can I write?

The question is not really how many personal statements you can write but how many personal statements you can upload to ERAS!

Let us consider first the scenario of an applicant applying only to one specialty. You can either do it the easy way and assign the same personal statement for all the programs you are applying to or you can modify the same personal statement to be more personalized for each program you are applying to and hence you can upload as much PSs you want.

Now let us take the scenario of an applicant applying to many specialties. Although you can upload for each specialty its own personal statement and, as stated above, you can modify it to personalize it to different programs, but here you need to be aware of an important thing; if you are applying to an advanced program which require application to PGY-1 spots then you need to use the same PS for both. This means if you also decided to apply to Categorical of that PGY-1 spot in the same program as well then they will be receiving the PS of the advanced program which is not good because it will show that you are interested in another specialty. Hence don't apply to Categorical and Preliminary spots in the same program if you are also applying to advanced programs in the same institution.