Tax filing basics
This section helps you understand the basics of filing your taxes, including what information you’ll need from last year and the key rules that apply to most taxpayers.
40 articles
- What are key federal tax filing dates for 2026 (Tax year 2025)?
- What do I need before I file my taxes? (Pre-filing checklist)
- Do I need to file a tax return?
- Can I file a return for a previous tax year?
- What's april and how does it work?
- How much does it cost to file with april?
- Can I enter an ITIN instead of an SSN?
- What’s the difference between AGI and modified AGI?
- How do I find last year's AGI?
- How do I find last year's tax return?
- What's an IRS IP PIN (Identity Protection PIN)?
- Where can I find my IP PIN?
- What if I lost my Identity Protection PIN?
- What's a Self-Select PIN?
- What personal info do I need before filing?
- What income docs do I need for filing?
- What info do I need to claim credits and deductions?
- Is my Social Security income taxable?
- What are april’s Maximum Refund and Accuracy Guarantees?
- How do I add or remove a dependent on my tax return?
- How do I find my prior-year AGI if someone else claimed me as a dependent?
- What do the different filing statuses mean in the app?
- What’s my tax filing status?
- What’s a Trump Account and how do they work?
- How can I find my AGI if I used a different tax platform last year?
- Where can I find my tax documents in april?
- What should I know about filing with april?
- How do tax extensions work?
- How do I request a tax filing extension?
- Do I qualify for an automatic extension?
- What are the penalties for late filing after an extension?
- How do I file a state extension?
- How do I calculate safe harbor for estimated taxes?
- How do I estimate my tax liability for an extension?