Dining Etiquette
The Costa Ricans, like all the people of Central America, are not punctual compared to many cultures so when you arrive for a meal will vary on your hosts or company. Generally speaking, arriving 15 minutes late is standard, although many locals may be as late as 30 minutes.
Once everyone arrives the meal will begin, but only after socialization time and perhaps a few drinks. After all, the point of dining with friends is to socialize so eating may take a back seat. Dress and seating are fairly relaxed in most settings, but your host may have a designated idea so let your host seat you. Before and with a meal you may be offered drinks such as beer, wine, or mixed drinks; you may drink if you wish, but there is little requirement to do so. Once you do begin eating, wait for you host to invite you to eat with the words "Buen Provechol."
As you begin eating, you'll notice the locals are pretty forgiving of foreigners breaking dining rules, but if you do want to fit in follow their lead. This may mean eating with your hands for some foods and if a fork and knife are required, eat in the continental style (fork in the left hand, knife in the right). It also means keeping your hands within sight at all times by resting your wrists on the edge of the table.
As your finish your meal, finish all the food on your plate and place your fork and knife together on the right side of your plate. The main meal may be followed by coffee and/or dessert.
If eating out, the person who invited the others out is expected to pay for everyone present. If this is you or you're just dining with foreign friends, also be sure to add a tip to the bill. In some restaurants a service change may be added, but this is not common; if there is no service charge, tip up to 10%.
Celebrations & Events
The holiday with food most closely associated to it in Costa Rica is Christmas, a Christian holiday celebrated by most of the population. This meal is usually focused on tamales, but pastries and numerous desserts, including the required tres leches cake are always present.
At most gatherings, whether it is for birthdays, anniversaries, or just large get togethers, food is usually served in a similar fashion. Appetizers tend to be abundant and if the occasion is special enough and large enough, may even justify roasting an entire pig. No matter the size though, all these celebrations require numerous sweets and cakes.
Drinks
Any popular beverage can be found in Costa Rica, including tea, juices, colas, and coffee. It is coffee that is the most locally popular drink and many of the coffee beans are grown in Costa Rica, but most of the country's best is reserved for foreign markets so tends to be weakly flavored and sweet. Local juices are also common, but are generally mixed with water or milk and have sugar to sweeten them; among the most common are mango, strawberry, watermelon, passion fruit, and lime. A couple more local drinks to try if you're in Costa Rica are granizado, which is a cherry-flavored shaved ice drink topped with condensed milk or aqua dulce, which is a hot beverage made from sugarcane juices mixed with water or milk.
Rum is perhaps the most popular alcohol in Costa Rica and the country distills a few of their own rums, including "Centenario"; however many locals and foreigners alike prefer imported brands. Another popular drink is beer, but again, few are produced locally. Although less popular guaro is an authentic local specialty, which is made from sugarcane and is served alone as a shot or mixed with juice. The local coffee-flavored drinks are also unique, including the brands of "Cafe Rica" and "Cafe Britt." Numerous other liquors and wines are also available, but few are locally produced or very popular.
The tap water is generally safe to drink in Costa Rica, but in more rural areas it should be avoided. The most cautious course of action is to entirely avoid the tap water and items that could be made from or with the water, such as ice, fruits, and salads. If you do decide to drink the local tap water, first check with your local hotel or guesthouse to learn the cleanliness of the water in that area. If the water is safe, remember that many people may have trouble adjusting to the local tap water as it will most certainly be different from what your system is used to if you are not from the region.