Post deleted by I'M GERMAN-IRISH

Welcome, G-I!
We never learn what happened to Willie Cicci. His testimony came before the establishment of the Witness Protection Program, so he probably got a reduced sentence and served it in isolation (probably a fairly comfortable cell by prison standards) at some Federal pen, much as did Joe Valachi after his Senate testimony.
Would Michael have tried to have him killed? Opinion here is mixed. Some say yes, because Michael never gave an enemy a pass, and Cicci, by turning rat, was an enemy. Others (including me) feel that Cicci wasn't a direct threat to Michael because he actually helped Michael by testifying that he never got a direct order from him. Others might counter by noting that Cicci did hurt Michael by testifying that "Michael Corleone was the head of the family." I'd counter by noting that Cicci may have lied (helpfully) when he said he never got an order from Michael--recall that, near the end of GF when Tessio's about to be taken for a ride, Cicci says, "Tom, Sal, the boss says for you to go on ahead...", indicating that he did get orders from Michael.
BTW: This question has been asked several times on this board. You can find previous answers by using the "search" function at the top of the page. I'm not trying to discourage you from posting, just alerting you to the wisdom of others.

In my opinion, I guess Michael gave the order to kill Willy, as Turnbull said, Michael never gave a pass. I don`t think Willy lied helpfully for Michael, all the things he said was on his own. Saying he is "the head of the family" is getting a death penalty for sure. I do belive Willy got a retribution from Michael whether in prison or outside...

I would suspect that Michael gave cicci a passs for several reasons. First, Cicci was, as Roth would say, "small potatoes." Second Cicci did help Michael by saying that he never got a direct order from Michael, although his snide comment about "buffas" wasn't much help. Third, Cicci was only there to lay the groundwork for the government's star witness, Pentangeli who was supposed to testify after they set the perjury trap for Michael. So my guess is that Cicci did some time in the pen, and was smart enough to keep his mouth shut and move on. Its possible that the Corleones got word to him that if he broke his silence Michael would be very disappointed. I imagine Willie getting out of prison and running some small time bookmaking operation for some small non threatening family someplace in New Jersey, getting caught and doing another term. I would put the character's death around the time of GF III the late 70's.

Welcome to the BB

Cicci escaped from prison, moved to Philly. He changed his name to Tony Gazzo and became a loan shark

Credible scenario, dt. And as an aside:
Willie Cicci is a relatively minor character in GF and II. But he gets an out-of-proportion but well deserved amount of attention on these boards. IMO, it's because Joe Spinell was so absolutely letter-perfect as Cicci, and made 200% use of the small amount of screen presence and lines given him. Alex Rocco's another example. Anyone ever accuse him of being a great actor? But he was terrific for four minutes as Moe Green. He and Spinell are prime examples of the brilliant casting for GF and II (and the lack of it in III ).

You are dead on the money TB....his acting was first rate...his body language in the scene where they are taking Tessio away, and again the scene where he says "That wasnt no heart attack" were brilliant.

I have to agree with you abou the lack of good casting in III. Even though it wasnt a great script some good aciting may have improved things. The oonly half decent performance by anyone was imho the Archbishop whe really came off as a detestable figure.