There is no specific prohibition against celebrating birthdays in Scripture, nor is there anything to indicate we should celebrate them. Scripturally speaking, it is a non-issue. The Bible does mention two individuals celebrating birthdays; the Egyptian Pharaoh in Joseph’s time (Genesis 40:20), and King Herod in the time of Jesus (Matthew 14:6; Mark 6:21). Some point to these non-believing individuals as evidence that celebrating birthdays is wrong, some form of pagan ritual. However, the Bible does not state, or even hint, that it was wrong for Pharaoh or Herod to celebrate their birthdays. Neither does Scripture anywhere discourage anyone from celebrating a birthday.
In his epistle to the Romans, Paul is addressing the issue of which day should be the day of worship, but this could also apply to birthday celebrations: “One man considers one day more sacred than another; another man considers every day alike. Each one should be fully convinced in his own mind. He who regards one day as special, does so to the Lord. He who eats meat, eats to the Lord, for he gives thanks to God; and he who abstains, does so to the Lord and gives thanks to God. For none of us lives to himself alone and none of us dies to himself alone. If we live, we live to the Lord; and if we die, we die to the Lord. So, whether we live or die, we belong to the Lord” (Romans 14:5–8).
The bottom line for Paul is that each man should be fully convinced that he is doing what God wants him to do. If one person chooses to celebrate birthdays and he sees nothing wrong with it, he should celebrate with a clear conscience. If, however, he feels celebrating is against his conscience, he should not celebrate. Conversely, if one does not celebrate birthdays for reasons of conscience, that is fine, as long as it does not become a source of pride and he does not look down on those who do celebrate. As with all issues not specifically addressed in Scripture, we have the freedom to celebrate or not celebrate birthdays, according to personal preference.
 Got Questions Ministries. (2010). Got Questions? Bible Questions Answered. Bellingham, WA: Logos Bible Software.