SAT/ACT Ivy League help?

Hi! I took the SAT a while back (plan to retake) and took 1 SAT subject test. I plan to take the ACT as it is more in line with how I solve problems, and hopefully will do better on that test. For ivy leagues such as Cornell, UPenn, and Columbia, do I need to send in everything (SAT AND ACT), or can I just send in my ACT with writing score?
Also, if I send in everything, does this mean I need to take one more SAT subject test (to fulfill the 2 SAT II test requirement)?

Sorry, my GC is not much help and I can’t seem to find this info clearly anywhere, as I don’t want to risk messing up!
Thank you!

Read the web sites. They are clear on what needs to be sent in.

E.g., https://undergrad.admissions.columbia.edu/apply/first-year/testing

@uesmomof2 Thank you! So, from what I understand, even if I take the SAT I can decide not to send it and instead send in my ACT score?

That is my understanding too but note that other schools have different policies. For example, Yale does not participate in Score Choice so you have to submit all scores from all tests. https://undergrad.admissions.columbia.edu/apply/first-year/testing

@uesmomof2 Thank you, I appreciate the help!

For purposes of qualifying for admission, Columbia, Yale, Penn and Brown require either ACT or, alternatively, SAT and two subject tests; Dartmouth, Cornell, Harvard and Princeton require two subject tests regardless of whether you submit SAT or ACT. That is the rule for qualifying for admission. A different and separate rule for each college is whether you must submit tests you have actually taken or can choose which to submit if you have taken multiple tests. Penn requires all test scores, SAT, ACT and subject tests. Yale requires either all SATs and subject tests or alternatively to both of those all ACTs; if you send any subject tests to Yale you must send all SATs. Cornell’s current rule is ambiguous but it appears you can submit either all SATs or all ACTs, plus all subject tests. All the other ivies allow you to send whatever tests you want to send.