Originally Posted by
serpens
Perhaps I missed other remarks, but I saw only one comment that mentioned the amount on which one might tip a percentage. In particular, if one believes in tipping a percentage, should it be on the menu price or the total check? I have some trouble seeing why the tip should go up because the local jurisdiction has imposed a restaurant tax, but I could be missing something.
On a slightly related theme, should one tip on a free meal? One example would be an Embassy Suites, where everyone gets a free breakfast. Tip the busboy? Another case would be a Hyatt Regency, where a diamond HGP member gets a complimentary breakfast. Tip?
Thanks for your thoughts.
The most common practice in the US is to calculate a tip percentage based on the undiscounted cost, not including any taxes. This applies to free meals, as well - tip is calculated based on the undiscounted cost. This is how I and virtually everyone I know calculate tips.
I personally modify this technique slightly for convenience: I round my tips up to the nearest even dollar when calculating a percentage, and for any bills under $15, I tip a flat rate of $3. To me, it seems silly to calculate a percentage of a $7.58 or $9.32 or $14.75 total, so I just put down $3 and call it square. Since this equals our to be at least 20% on those small tabs, everyone is happy - I don't have to use my calculator, the server gets a fair percentage, and nobody has to deal with coins. At self-service buffets, I always tip a flat rate of $2. Since about 90% of my restaurant eating is alone, and mostly with costs under $15, this makes my tipping practice simple and automatic (assuming adequate service).
Some people use different systems, such as calculating based on the cost after discounts are applied, or calculating based on the total cost including taxes. But the general practice is, don't increase tip due to tax, and don't decrease tip based on coupons, discounts, or complimentary items. I have even seen some people tip a flat, set amount, regardless of the size of the bill (which inevitably turns out far smaller than what a percentage-based tip would be).