There might be other people that belong on your return, other than your spouse. You will need to have the dates of birth and social security numbers for these individuals. For example, you’ll need childcare records (including the providers ID number) if applicable. You will also need the approximate income of other adults in your home (not spouse, if you’re filling jointly). Additionally, have on hand Form 8332, copies of your divorce decree, or other documents showing that your ex-spouse is releasing their right to claim a child to you. You can learn more about what you need to file your taxes here: What do I need to file taxes?