For a $400 dinner in a full-service U.S. restaurant in 2026, a standard tip ranges between $72 and $100. This follows the current industry norm of 18% to 25% for table service. An 18% tip, considered the "base" for acceptable service, would be $72. A standard 20% tip, which is the most common expectation for good service in fine dining, totals $80. If the service was exceptional—common at the $400 price point where you often receive personalized attention from sommeliers and multiple servers—a 25% tip of $100 is appropriate. It is worth checking your bill for an "automatic gratuity," as many restaurants now include a 20% service charge for large parties or high-check totals. If you are tipping on a $400 bill, it is generally recommended to calculate the percentage based on the pre-tax subtotal, though tipping on the post-tax total is considered a generous gesture that many waitstaff appreciate, especially since they often share their tips with back-of-house support staff like bussers and runners.