Didn't file Federal 1040 for 2016 yet because I'm still waiting for a K-1. Should I file without that information and amend later or wait a little longer?

If you have a refund due at the federal and state level, then wait for the Schedule K-1.

If you OWE taxes, then file and amend later.

Thanks!

Glad to help!

I am in the same situation, but what I do is apply for a filing extension, which gives you till October to file your 2016 return. If you owe money it should you have been paid by April 15, using the estimated tax payment form. Complete your Form 1040 once all K-1's are received, before the October deadline.

Hope it doesn't take that long!