Should you bring a separate gift if you're invited as a plus-one?
This greatly depends on your relationship to the bride and groom. Though you're never technically required to bring a gift, it's highly recommended you do and it's considered a sign of congratulations and thanks to the couple for involving you in their special day.
As a rule of thumb, spend less than $100 if you're not a close friend. The same rule applies if you're a plus-one. Since you are attending, it would be very kind to get something small. Consider going in on a gift with your date, or buying something complimentary. For instance, if your date buys those nice salt and pepper grinders off the couple's registry, consider buying some organic sea salt and whole peppercorns to go with it. It's not a very expensive gift, but it's a small gesture that will go a long way with the bride and groom (and your date).
Find any couple's registry here.
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