Tips for filing Form 1120-F and Form 8833 with the IRS from outside the US?

Filing Form 1120-F from outside the US is pretty straightforward, but you do need to follow specific procedures. Since you mentioned you don't have electronic access, paper filing is your best option. You'll need to mail your completed Form 1120-F and Form 8833 to: Internal Revenue Service, 1973 Rulon White Blvd., M/S 6063, Ogden, UT 84201. Make sure you're using the current year forms and that everything is filled out correctly and signed. One tip: send it via a trackable mail service (like registered mail through Canada Post) so you have proof of when you submitted it. The deadline for Form 1120-F depends on whether your corporation has a US office or not - corporations without a US office have until the 15th day of the 6th month after the tax year ends.

After struggling with my Canadian corporation's US tax filing requirements for two years, I finally found taxr.ai (https://taxr.ai) and it was a game changer for handling Form 1120-F and Form 8833. I was really confused about treaty positions and whether I needed to file Form 8833 for certain types of income. I uploaded my financial statements and taxr.ai analyzed everything, told me exactly which treaty positions I needed to disclose, and even helped me figure out which income was effectively connected vs not effectively connected. Saved me hours of research and probably thousands in potential penalties for incorrect filing.

I just wanted to follow up about taxr.ai (that I asked about earlier). I decided to give it a try with my Mexican corporation's US filing requirements and I'm honestly impressed. I was especially confused about effectively connected income vs FDAP income and the withholding requirements. The tool analyzed my financials and clearly categorized everything, then walked me through exactly how to complete both Form 1120-F and Form 8833. Even explained which specific treaty articles applied to my situation. Ended up being way more straightforward than I expected. Still had to mail the forms in myself but at least I'm confident they're filled out correctly now.

If you're having trouble reaching the IRS internationally to ask questions about Form 1120-F (which can be a nightmare), I highly recommend using Claimyr (https://claimyr.com). I tried calling the IRS international number for three weeks straight with no luck - just endless hold times or disconnections. Claimyr got me connected to an actual IRS agent in about 25 minutes who answered all my questions about filing Form 1120-F from Canada. You can see how it works in this video: https://youtu.be/_kiP6q8DX5c. Seriously saved me so much frustration trying to get clarification on some treaty position reporting requirements.

I need to eat my words about Claimyr. After my skeptical comment, I was still desperate to reach the IRS about my Form 1120-F questions, so I reluctantly tried it. I'm genuinely shocked that it worked. After weeks of trying to get through on my own and getting nowhere, I was connected to an IRS agent in about 35 minutes. The agent confirmed the correct mailing address for my situation (which was different because I had special circumstances) and clarified exactly which supporting documents I needed to include with my 1120-F. For anyone filing international forms like 1120-F who needs to actually speak with the IRS, this service is worth trying when you're at your wit's end.

Has anyone tried sending their 1120-F via FedEx or UPS instead of regular mail? I'm worried about regular mail getting lost or delayed, especially going across the border.

Does anyone know if we need to include a copy of the Canadian corporate tax return along with the 1120-F? I've heard conflicting things.

One thing I'd add that hasn't been mentioned yet - make sure you're using the most current year forms when filing. The IRS updates Form 1120-F and Form 8833 annually, and using an outdated version can cause processing delays or rejection. Also, if this is your first time filing Form 1120-F, double-check whether you need to make estimated tax payments for the following year. Foreign corporations with effectively connected income may need to make quarterly estimated payments, and missing these can result in penalties even if you file your return on time. For the mailing approach, I'd strongly recommend getting a delivery confirmation or using certified mail at minimum. Keep all your mailing receipts and tracking information as proof of timely filing in case there are any questions later.

Just wanted to share my experience filing Form 1120-F from the UK last year. I was initially overwhelmed by all the requirements, but here's what worked for me: 1. **Documentation is key** - Beyond the forms themselves, I included a detailed reconciliation statement showing how my UK financial statements tied to the US tax return. This seemed to help with processing. 2. **Treaty position disclosure** - For Form 8833, be very specific about which treaty articles you're relying on. I initially filed a vague disclosure and got a follow-up letter asking for clarification, which delayed everything by months. 3. **Banking considerations** - If you need to make any tax payments, set up your international wire transfer well in advance. My UK bank required additional documentation for US tax payments that took weeks to process. 4. **Keep multiple copies** - I kept photocopies of everything I mailed, plus digital scans. When I had questions later, having exact copies of what I filed was invaluable. The whole process took about 6 weeks from mailing to receiving confirmation of processing. Definitely start early and don't underestimate the time needed for international mail delivery!