Surah Baqarah verse 63.
Surely, the Believers, and the Jews, and the Christians and the Sabians — whichever party from among these truly believes in Allah and the Last Day and does good deeds — shall have their reward with their Lord, and no fear shall come upon them, nor shall they grieve.
But you could say all the groups listed at the beginning of the verse including Muslims have to meet the conditions stated that start with the belief in Allah for them to have their reward. Remember, by claiming to be a muslim alone doesn't guarantee one to have heaven for a reward, people have to keep the covenant and promises they make to their God when they declare faith in Him. All of these groups can negate their belief with their actions, and some of them did already just that.
When you pick a subject about something using the Quran, you do research so that you bring all related verses that are spread throughout the Quran. An example of what I mean is; Allah states Christians have violated a main tenet of their faith when they claimed Jesus was the biological son of Allah, it states in the Quran for that claim, the heavens could go asunder and split for the sheer sinfulness of that claim(Metaphor to show how big of a sin that is) and how much Allah finds that to be beneath him to have a son. They are declared disbelievers for that reason even though still Islam calls them the people of the book.
If everybody was heaven bound who said they believe in God, then there is no point for upholding declared beliefs. There would be no point in Islam itself. Because Islam claims that it is here to correct and guide people back to the original message earlier nations screwed up.