That is a real choice, not a formality. Some households send the investor first so the enterprise can be developed and directed, while the spouse's history is reviewed. Others wait. Decide it with counsel, because a separated arrival affects schooling, income, and how long the family plans to be apart.
Price the separation before you choose it
Compare duplicate housing, childcare and the spouse’s actual employment plans under different arrival dates. If proposed United States earnings depend on E spouse status, confirm that status and accepted work evidence before employment begins. Existing independent work permission needs separate review. The principal’s approval does not guarantee the spouse’s result, and E dependent children receive no work permission from their status.
Decide which spouse will be the principal before the ownership documents are drafted, because that person's name should appear on the share register with the controlling interest or the documented operational authority. A spouse in valid E derivative spousal status may be employment-authorized incident to status when the required admission evidence supports that classification. A qualifying E spouse may work incident to status, but should preserve the documentation reflecting that status before beginning.
A joint account may establish access or entitlement to funds, but it creates no U.S. status for either spouse.