If you finish your plate, you will surely be offered seconds and thirds. Turn down this food at first; only after your host's insistence should you succumb to their offerings. If you truly are done, place your knife and fork together.
If eating at a restaurant, the inviter pays for everyone, but you should offer to assist, although this will most likely be turned down.
At sit down restaurants with a waiter or waitress, round up or tip about 10% of the bill, but tip at your discretion and in Romania you'll probably need your discretion since service isn't one of the country's strong suites.
Drinks
Romania has all the world's most popular drinks, but adds a couple more unique beverages. Sadly, there are few original non-alcoholic drinks in the country, although all the popular drinks are available, including tea, coffee, juices, soft drinks, and milk.
Among the alcoholic beverages, the Romanians get more creative. Many people distill alcohol at home and these drinks can be made from any number of different fruits and berries. One example, palinca, is a fruit brandy with an alcohol content well over 50%. Wine and beer are also popular, particularly beer among the ethnic Romanians and wine among the ethnic Hungarians. In addition to these, all popular alcoholic beverages are widely available.
Generally speaking, the tap water is safe to drink in Romania, but check with locals for any particular regional differences. Also, many people may have troubles adjusting to the local tap water, as it will most certainly be different from what your system is used to.