Here is an English version of our post (in Italian) about suggested addresses to drink and “nibble” in Rome.Mainly not touristic destinations, but places where Romans (including us!) love spending time before dinner (and sometimes even lunch).
Groups by categories are used as in the other posts in English we wrote about brunch and pastries. Choose yours and we appreciate if you want to join us with comments and suggestions. Clubs where you can stay until late evening and dance are not included, maybe we will write a specific post for these! 
Drinks – the actual protagonists for Roman apéritif – are often combined with food, sometimes with a free buffet some others with a single plate of snacks. It depends on how the place personalizes the “moment”. For each address we provide a short description of the food they offer.  
Romans’ preferred days for happy hour are Sunday and Friday but also Thursday is becaming popular.
Follow the links to access web sites or map to get there. Unless otherwise specified, supply of food is included in the drink price during Happy Hour (usually at least between 7pm and 8pm with a cost around 10€).
Trendy – cute places to enjoy drinks in a fashion & “chic” environment
1) eTablì: behind Piazza Navona it has a characteristic Provencal furniture. Small plates of appetizers are offered to accompany drinks. Atmosphere can justify prices above average and service sometimes is in a rush.
2) Il Bar del Fico: a recently renovated cute place in the hearth of historical center, with modern and refined interiors. During happy hour a really “mini” buffet is available, including mostly souces, vegetables and focaccia.
3) Salotto Locarno in the lobby of the homonymous hotel in via della Penna, right next to Piazza del Popolo, this is a highly popular place with its “Orient Express” interior environment and amazing courtyard. Free finger-food plates prepared by the hotel restaurant La Scena are served with drinks (quite expensive, cocktails up to 13€). In the last visit few days ago we had terrible service but you don’t come here for this. 
4) Salotto 42: just in the charming Piazza di Pietra it is another historical “sofa” in Rome, with its eclectic and northern European atmosphere. Serves bio tastes along with drinks.
5) Doppio Zeroo: away from downtown, in south Rome Ostiense area. It remains a reference over time for happy hour and it offers a rich free buffet mostly based on slices of pizza, with traditional ingredients and sweet with nutella.
6) Duke’s: in the “chic” Parioli district, it always serves good cocktails (appetizers not available) even after dinner that you can also have in the restaurant area.
Vintage – full immersion in atmosphere and furniture that recall ’60s & ’70s
7-8) Necci dal 1924 in the “young” and multicultural suburb off the tourist tracks Pigneto and Il baretto in via Garibaldi just above Trastevere. They both offer a small free buffet and are extremely cool with good weather because of their pleasant outdoor spaces.
Wine – careful selected labels available also by the glass together with quality appetizer
9) Fafiuchè: in Monti District close to the Coliseum. Small place (about 20 seats) with wine bottles on the walls and a delicious buffet prepared by the owner. A single plate is included in the drink fixed price.
10) Trimani Wine Bar: historic address in Rome for wine tasting and bottles supply, located not far from Termini station. Food is not included in the offer but you can order few dishes from the menu (it is a restaurant too).
11) Enoteca Provincia Romana: amazing location opened about 1 year ago in front of Colonna Traiana and Fori ruins, managed by the Provincial Administration. It’s possible to select local wines and delicacies (not included in the drink price) from the menu with a good quality/price ratio.
12) Vineria Anzuini: in south of Rome Eur business area, glasses of wine are accompanied by a free buffet mainly with salami, cheese, pizza and focaccia.
12b) Remigio: some of our trusted Italian readers suggested to add it to this list, consequently we decided to include it in the English version also if we have never been there. It is located far from downtown in Tuscolanaarea (via S.Maria Ausiliatrice 15). Champagne is the “star” and a wine selection is also available, with a free buffet changing every day.
Beer – almost complete devotion to the beer, mostly crafts
13) Open Baladin: in historical center (via degli Specchi) a cute place with more or less 40 draft beers from the famous Italian producer Baladin and not only. Food has to be ordered in addition and the choose is among homemade chips, hamburgers and other plates including some slowfood raw material, but quality in our opinion is not at top. The main large room after the entrance is vociferous and if you are two people we suggest to ask for a table upstairs that is much more quiet.
14) 4:20: located where Porta Portese market is held every Sunday morning, a pub and restaurant where everything is based on craft beer. It is possible to enjoy the large terrace during spring and summer but also in winter the internal atmosphere is nice. Food to be ordered and paid additionally to beers.
Young – best for under 30 people
15) Freni e Frizioni: in Trastevere near to Lungotevere, a meeting point for tourists and Romans since many years. During summer the pedestrian square in front becomes really crowded. Happy hour with cocktails, wines by the glass and beers with a free vegetarian style buffet.
16) Micca Club: few steps from Piazza Vittorio, a young, vibrant and lively environment balances an average quality food offer. Many theme nights are organized, including live music and burlesque.
17) Momart Cafè: in the University area, near to Piazza Bologna, spacious and modern rooms where drink are accompanied by an abundant free buffet, predominantly with pizza.
New – recent openings or renewals
18) Settembrini Caffè: located in Prati (piazza Mazzini) district it is one of the most loved addresses by Roman foodies. Good wine glasses selection, spumante or cocktails are served with homemade chips and some appetizer changing every day. Coming soon a happy hour more oriented to beers in the new place from the same property – named Set’ – located just in front of the café.
19) Coffee Pot: in via della Lega Lombarda (University area) a vintage atmosphere given by second-hand objects well distributed in the cool space. You can stop here all day from morning to night and even though there is no real happy hour you can order some cold food or setup an appetizer buffet for groups upon request. One think we don’t like however is that despite the name it is not possible to order a cup of tea or coffee in the evening!
20) Panella: it is an old famous (and high-end priced) bakery in Rome located in via Merulana (between Piazza Vittorio and Coliseum). We have included it in the “New” section because it has – few months ago – renovated space and happy hour offer, consisting of a free appetizer buffet prepared from the kitchen and bakery.