SAT Subject Test Scores

I’m planning to take the subject tests for Biology E/M and Math 2 in August. If I do get a “low” score (under 650 or so…?) how much will that hurt me in the admissions process? I plan to apply to mostly UCs, where the subject tests aren’t mandatory to start with. My highest SAT score is 1360/1600 and I plan to major in a biological science (physiology, human biology, something along those lines)

Thanks to anyone that can help!

For the UCs, it won’t hurt you as you don’t have to report them. In fact, I’m not even sure a high score helps. (My son scored 790). UCs care more about GPA, rigor and ECs.

Thank you so much!