Mailing a check is fine! But you cannot just write “IRS” on an envelope and hope for the best. You need the specific address based on where you live and which form you’re paying.
This is where it gets annoying. The IRS has different mailing addresses for different states. They really don’t make it simple.
Don’t guess. Look up “Where to File” on IRS.gov and use their tool. It asks for your state and the form number (like 1040). It spits out the exact address.
The Envelope Rules (Yes, There Are Rules.)
Write a clear, legible check. Make it payable to “United States Treasury.” Not “IRS,” not “Uncle Sam.” United States Treasury.
On the memo line, write your Social Security number or tax ID, and the tax year (e.g., “2026 Form 1040”). This is critical. They will lose it without this.
Include the payment voucher (Form 1040-V) if you have it. If not, just a note with your info works—but the voucher helps the robots process it faster.
