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As a follow-up to this question: Wash sale rule impact on different scenarios between different types of accounts
Do HSAs and 401k's fall under the same treatment as IRAs when computing tax losses?
For instance, your HSA and 401k are set to allocate biweekly contributions and reinvest dividends for a Fund X resulting in a total of 50 shares purchased during the 30 days before and 30 days after a sale of 100 shares of Fund X in your personal brokerage account. Does the loss in the personal brokerage account only apply for 50 shares of Fund X?