I've heard the Salvation Army is kind of terrible.
https://archive.attn.com/stories/17044/why-woman-says-you-shouldnt-donate-salvation-army
This is just one experience but it makes me wary.
Also, don't give to the ASPCA or the HSUS, they spend more on advertising than they do on helping animals. Give to local animal shelters instead. Donate food and time if you can.
Many big charities don't actually help what they claim to, it seems. If you want to help the needy in your community, donate directly to smaller local charities. I am not sure how many is "many", not trying to make a blanket statement here. I guess the best bet is to research the charity. And use sources that aren't affiliated with it. Ask the groups they say they help.