Twenty days, I normally give them 40 days to be safe to file for an uncontested divorce.
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The big question is whether the failure to respond is intentional pursuant to an uncontested divorce by agreement, or whether the other spouse is just being non-responsive. Courts readily reopen default judgments if the defaulting party has a good reason, as public policy dislikes default judgments. However, the other attorneys are correct regarding the time to respond, and assuming that your spouse was personally served.
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