Biblical scholars do not agree on the number of epistles that Paul wrote; some think he wrote all 13 epistles that have his name on them, while others think he authored only a few of them. The Letter to Hebrews used to be attributed to Paul, but now few scholars believe he is responsible for writing it.
Conservative Bible scholars think Paul wrote Romans, 1 and 2 Corinthians, Galatians, Ephesians, Philippians, Colossians, 1 and 2 Thessalonians, 1 and 2 Timothy, Titus and Philemon.
Others believe that it is only accurate to assign his authorship to Romans, 1 and 2 Corinthians, Philemon, Galatians, Philippians and 1 Thessalonians. They think he may have only written parts or none of the other epistles due to changes in writing style and content.