When it comes to tipping at a wine bar, the United States has not established a definitive answer. If the restaurant does not include a service fee, it is expected that waiters receive lower hourly wages and tips should make up the difference. Generally, 18% is the minimum, 20-22% is the norm, and a good experience should cost 24 to 25% or more if you're feeling generous. In large groups, an included tip of 18-22% is common.
However, if you don't feel like a specific wine and don't know the wines on the list, it is best to communicate with your waiter. If you are knowledgeable about wine, you may not need help navigating the list. However, it is important to be mindful of your fellow customers and not show off your wine knowledge in an arrogant way. Plus, there's no need to tip unless you've had an extra incredible experience.
Keep an eye out for the included tip to make sure you don't double tip. Allow me to give you an expert opinion on the subject. Learning the guidelines of wine service will allow you to enjoy great wine and avoid falling into typical (and embarrassing) mistakes.