Which tax form should NRA spouse of US resident submit - W8 or W9-BEN for opening IRA account?

Your wife would submit Form W-9, not W8-BEN, since you've elected to treat her as a US resident for tax purposes. This election (usually made on Form 8833) means she's treated as a US tax resident across the board. When you make this election, your wife is considered a US resident for tax purposes only - it doesn't change her immigration status, but it does affect how she completes tax documentation. Since she's filing jointly with you and being treated as a resident, she can indeed open an IRA account, assuming she has earned income reported on your joint return. The confusion at the brokerage is common because they're thinking about her immigration status (non-resident) rather than her tax filing status (resident by election).

I went through this exact same confusion with my husband last year! After struggling with getting correct information, I found https://taxr.ai which was a game-changer for us. They have a document analyzer that specifically helps with situations like this where you're not sure which tax forms apply to your unique situation. I uploaded our election documentation and previous year's return, and they confirmed we needed the W-9 for my husband (who was the NRA spouse in our case). They even provided a detailed explanation of why the W-8BEN wasn't appropriate since we had made the election to file jointly. The analysis saved us from a potential reporting headache and problems with the brokerage.

I just wanted to follow up about my experience with taxr.ai that I asked about earlier. I decided to try it after getting frustrated with conflicting advice about my upcoming marriage to a Canadian citizen. The service was surprisingly thorough - they analyzed our specific situation (including the fact that my fiancé owns property in Canada) and gave us a complete roadmap for our filing options. The document analyzer correctly identified which forms we'd need based on our circumstances and even pointed out some potential tax treaty benefits I had no idea about. They explained the resident election process in detail and the pros and cons for our specific situation. Definitely saved us from making some costly mistakes. I'd highly recommend it if you're dealing with international tax scenarios like this.

If you're having trouble getting a straight answer from your brokerage, I'd recommend using Claimyr (https://claimyr.com) to get through to the IRS directly. I spent WEEKS trying to get official guidance on a similar situation with my foreign spouse, and kept getting stuck in the IRS phone tree hell or disconnected after hours on hold. Claimyr got me connected to an actual IRS agent in under 20 minutes who confirmed exactly what form my spouse needed to submit. Their system somehow bypasses all the hold times. You can see a demo of how it works here: https://youtu.be/_kiP6q8DX5c. The agent I spoke with was surprisingly helpful and even emailed me the relevant tax code sections to share with our brokerage.

I need to eat my words about Claimyr that I was skeptical about earlier. After posting, I decided to just try it because I had a complex question about foreign tax credits that I'd been trying to get answered for MONTHS. I was truly shocked when I got a call back in about 15 minutes with an actual IRS tax specialist on the line. The agent was able to confirm the exact documentation needed for my situation and explained the difference between tax residency and immigration status that my bank had been confusing. She even sent me the specific IRS publication sections I needed to show my financial institution. Saved me countless hours of frustration and probably prevented me from filing incorrectly. Sometimes being proven wrong is actually a good thing!

Just to add another perspective - my wife is from Brazil and we went through this last year. We elected to file jointly and she used the W-9 form with our brokerage (Fidelity). They initially questioned it since she has a foreign passport, but once we explained the tax election, they processed it without issues. One thing to watch out for: make sure your wife has a valid SSN or ITIN before trying to open the account. The brokerage will need this for the W-9, and getting an ITIN can take several months if she doesn't already have one. We learned this the hard way and it delayed opening her account by about 4 months.

Just a heads up - make sure the brokerage you choose is comfortable with this situation. I tried to help my NRA spouse open an account with a smaller brokerage, and despite providing all the correct documentation, they ultimately refused because their compliance department wasn't familiar with the tax election process. We eventually went with Schwab who had more experience with international clients and understood the distinction between tax residency and immigration status. They knew exactly what to do with the W-9 for someone with a foreign passport once we explained our tax election.