IRS Revenue Ruling 2008-5 prevents investors from using the cloak of a tax-deferred account type such as an IRA to circumvent the wash-sale rule. It applies to traditional and Roth IRAs, regardless of whether the IRAs are held at different financial institutions.
https://www.investopedia.com/articles/retirement/09/ira-wash-sale-rule.asp
- If a security is sold in a non-retirement account at a loss, then an identical investment is bought in an IRA, the result is a wash sale.