Extension filer's checklist
- Last year’s tax return, federal and state
- W-2s, 1099s, and any letters marked “important tax document”
- Mortgage interest and property tax statements, if you own
- For business owners: your year-end books, or the shoebox (I’ve seen worse)
- A photo ID, and Social Security numbers for anyone on the return
- Your extension confirmation (Form 4868), if you have it handy
- Any estimated payments you made since April (amounts and dates)