Many visitors who are not familiar with American customs are often at a loss when it comes to tipping and gratuities. Although this is not a definitive guide, it will get you on your way.
1. First a tip is also known as a gratuity. It is certainly not mandatory. Perhaps the best way to think of a tip, is to think of it as a “thank you”. You are thanking the guide/server for good service. Tip nothing for bad service and tip well (20%) for great service. Tip in between for everything in between. Many NYC restaurants add a service charge to your bill whether you are a party of two or a party of 10. Check the bottom of your bill. If a service charge has been added be sure to write ZERO in the credit card bill. The service charge is an imposed gratuity; there is no need to add a tip on top of a tip, unless the service charge was under 15% and the service was exceptional. In this case top it off to 20%.
2. Although certain industries expect a tip (restaurants, tour guides, etc). There is an unwritten rule that you should never ask for a tip. It’s considered uncouth. If someone asks you for a tip consider not tipping at all. Again, if a tip is a way to say “thank you”. How would you feel if someone asked you to thank them? Especially for bad service.
3. Don’t be embarrassed to leave a tip! You do not need to hand the gratuity to the person discretely. That’s like leaning over and whispering “thank you” in their ear as you leave. Unless they or you are doing something illegal, there is no need to “whisper”. Again it’s just a “thank you”. Also, don’t be embarrassed if your tip is rejected. They are just letting you know that it’s not necessary – no harm no foul.
4. What if you forgot to tip? If you forgot to leave a tip and the service was exceptional leave a review on tripadvisor.com . Mention the server/guide's name specifically so their boss knows they are doing a great job. A 5 star review is often worth more than the tip. It helps the business grow which means you are also helping whoever served you keep their job and earn more tips