If you are looking for somewhere to have a drink and a good time then check out below.  There are quite a lot of bars and what to expect in each but it is by no means an exhaustive list. Feel free to add more if you wish. (This information has been taken from various sources, please note this is not a personal recommendation).

Bikini G's
Starco C.C.
The main theme of the bar is beachwear not just with the ladies in bikini's but the gents in their Speedo's too!  The DJ is a female and will spin pretty much anything that you fancy and will make sure all the party goers are getting involved. If you’re not interested in dancing then you can shoot some pool on the in-house table.

Bar 39
Near Paradise Hotel/Royal Palm
Los Cristianos Heights

Excellent food and entertainment.

Bentley's Bar
Playa de Fanabe

British owned very good selection on the food, nothing is too much trouble and it over looks the beach.

Bluebell Bar
Los Cristianos

The drinks are very reasonably priced and there is entertainment on most nights.

Brannigans
Starco C.C.
Under Tramps and Next Door but one to Rags

One of the things people remember about Brannigans are the drinking games. Throughout the night the DJ will do numerous games and challenges, which are funny to take part in and even funnier to watch.

Colon Beach
Puerto Colon
Cabaret Bar with really professional entertainers Innuendo (Donna & Les). who perform 7 nights a week. Regular cabarets from Elvis, Freddy Mercury, Neil Diamond, The Beatles and a great Rock n Roll night.  This bar attracts the best performers on the island as it is the only place they come to make live recordings of their new DVDs so whenever you go there is always a quality show.  Professional website where you get free downloads of the photos taken the night you were there www.innuendotenerife.com

Celts Tavern
Upper Floor,
C.C. Bouganville, Pueblo Canario
Playa de Las Americas

The place to get in a bit of line dancing practice.

Chessies Bar,
El Colonel
,
Los Cristianos (near Studio 5 hairdressers and The Bluebell Bar)
Great Scottish Bar showing all Scottish football games. Friendly staff and the cleanest toilets in Tenerife. Quiz nights on Mondays. Occasional live music and Karaoke.  Reasonably priced drinks and great Toasties.

Christy O Connors Irish Bar
Opposite Playa Azul, Playa de Las Americas

Live entertainment, Major sports and GAA games on 7 TVs and 2 metre screen

Geordie Pride
Puerto Colon
A friendly family bar with good music and a chance to watch whatever you want on TV.  Excellent food and drink at reasonable prices, Caters for all ages. Right above the beach so you can nip up and down all day,.  Taxi rank at the top of the stairs so easy to get back to your hotel.

Divine Soul – (formerly Jazzisimo)
Opposite Leonardo’s, Playa de Las Americas
If you are looking for a nice laid back night out this is the place for you.  A great night out with a difference.  See the Four Tops, Temptations and the Supremes shows. The venue is luxurious so ‘dress to impress’. Check the website but it is still under construction as this is a brand new project. Hope it is a bit cheaper than Jazzismo as their soft drinks were €4.20 www.divinesoultenerife.com

La Gramola Bar.
Las Galletas.
Anyone who walks in this bar and quotes Treble99 can have a buy one get one free offer. (This applies to your first visit and for 1 hour only)

Leonardo’s
CC Paraiso Royale, Playa de Las Americas

Leonardo’s is known as the Nº1 Meeting Point. Once you’ve been in, you’ll appreciate why. Showing TV during the day and live music at night and live entertainment from the World Famous Wild Boyz, just a 2 minute walk to Veronicas and Starco. Drink prices are a lot cheaper than down the road.

Linekers Bar
Starco Centre
Playa de Las Americas
The World Famous Linekers Bar part of a chain around the Canary Islands owned by Gary Linekers brother where you can be entertained by top DJ´s whilst rubbing shoulders with a host of celebrities.   Experience a real stadium feel with 26 screens showing all football & sporting events from around the world in fully air conditioned surroundings.

Magic Bar
Next to the Piramides,
Playa de Las Americas
Owned by the same group as Harry's Cocktail Bar and the American Pie Restaurant, this is a really up market bar where all the 'in crowd' will gather.  Opened less than a month ago it is already betting excellent reviews in the newspapers.  Alcoholic drinks, cocktails and non-alcoholic cocktails are around €7 but the ambiance really makes up for the prices.  There is live music every night from around 9.30 pm.

  

The Mett Bar
Ground Level of Starco C.C. opposite Edwards

A decent size bar and they encourage dancing on chairs. This is a wicked place to go anytime after 12am. The music is great 90's classics, Commercial R'n'B, Chart.

Murphy’s Irish Pub
Torres de Jomely, Playa Las Americas

Live music from 9.00pm till 1.30am and sports channel daily.

O’Brien’s Irish Music Bar
C.C. Puerto Colon, 1/F, Las Americas
Live traditional Irish music every night from 9pm to 12.00am.
 
O'Neills
Upper floor, Veronicas
This is the jewel in the crown of the bars along Veronicas Strip and offers something musically different from the other bars. The air conditioned inside bar is the place you go to dance to all the latest funky house, classic dance and R'n'B and there is minimal seating area here so you have plenty of room to get your groove on. Great staff who are very welcoming. Brilliant prices too.



Shenanigans
The Patch, Playa de las Americas,
In-house band 'Looney Tunes' are very good a wide range of ages drinking there.

St. Eugene’s Bar
Playa del las Americas

The regular compere Mike Charlton is very funny but if you are easily offended then it is not the place for you.
 
Snoopy's Pub
Underneath Laguna Park 1, not far from the water park
San Eugenio
Enjoy the craic, the singing and karaoke but be careful the cocktails are lethal.

Shakespeare’s,
Los Cristianos,

A good atmosphere with quizzes and karaoke every night. Kids magician Saturday’s and a Rod Stewart tribute on every Tuesday night at 10pm.

Scoffs
Sunset Bay
Los Atamanes, Torviscas

Offering English breakfast, bar snacks, bar lunches, and a Special Sunday Lunch. There is a large open-air terrace with pool tables.

Scotties Cabaret Family Bar
C.C. Starco
Las Americas

Cabaret acts, quizzes, Sky digital and more in air-conditioned comfort.

The Premier Bar
Amarilla Golf

Good food, good entertainment and is run by a great couple. The cabaret each night - although it doesn't start until 11pm, is absolutely brilliant.

The Corner Bar
Parque de la Paz, Las Americas
Opp. Mediterranean Palace

Live entertainment and British food.

The Irish Fiddler
Los Geranios, San Eugenio
Live music every night at 9.00pm a well known Celtic Bar with lots of memorabilia and an atmosphere to match

The Trapdoor Sports Bar,
Guayero, Los Cristianos.
This is the only place  to watch any sporting event. 7 TVs, giant projector screen and plasmas. Showing several different footy matches at the same time with great supporter banter. Great atmosphere, quizzes and really good food. Pool table and darts. Everyone is made to feel welcome. Towards the beach from the Princesa Dacil Hotel, next door to the Oasis Moroque hotel and opposite the crazy golf.



Legends Bar (Formerly Crooked Spire) 
Pueblo Canario -Inside The Courtyard
Playa de Las Americas

The bar offers fun and entertainment for the whole family with your resident host and compere Deano, and is always packed with both tourists and residents.  You can watch the islands top cabaret acts every night of the week, or even perform yourself during the karaoke, which goes on til 2am. Plus watch all the live sporting events on their 2 metre screen or on one of the seven big screen Tv's. In the courtyard/beer garden you can play pool or table football or just relax in the sun as its a great sun trap.

View Into Legends 
Legends Staff On Halloween Nite

The Bus Stop
Owned by Scott (also a partner in the Royal Oak II next door), the Bus Stop caters for families, however it tends to provide 'younger' entertainment in the evenings, with music, compare and a touch of karaoke

The Dubliner Bar
Under the Las Palmeras Hotel near the Patch, Las Americas.

This Irish theme pub is open from 9pm til 5am and offers a wide range of drinks. From 10.30pm til 3am there is entertainment from the best band in Tenerife. They give a range of music from typical Irish songs through to the latest chart hits (Kooks/Artic Monkeys/Kaiser Chiefs and more).

The Full Monty Fun Pub
The Patch, Playa De Las Americas
Live entertainment and cabaret every night, starting at 8:00pm.

The News Cafe,
Torviscas
A good night out at low prices, unlike many bars The News Cafe has an international flavour with singers and drinkers from Scandinavia, mainland Europe and Russia etc.

The Princess Di Pub
The Patch, Las Americas
Live entertainment every night, large selection of British beers, latest films shown in the daytime and all major sporting events shown on the big screen.

The Royal Oak II
Down from Oro Blanco/Negro
Co-owned and run by Andy, avid Brighton & Hove Albion and CD Tenerife fan, all your football, drinking and eating requirements will be fulfilled. 6 screens for sports and basically show every game it's possible to get. 
If you fancy seeing CD Tenerife play in a live footy match, have a word with the bar staff, as they runs coaches to and from the games.
Entertainment starts at 9pm nightly and consists of decent tunes; one night a week they have comedy hypnosis, which is a laugh. Within staggering distance of Veronicas and Starco, so is an excellent place to start of finish your evening if you're a party person, however the bar does tend to cater more for families

The Soul Suite
Parque De La Paz
Mediterranean Palace, Las Americas

Listen to Joe Harriet sing, seven nights a week.

The Thirsty Beggar
Local 4,Malibu Park
Avenida Austria, San Eugenio Alto

Located opposite the Waterpark, Nightly entertainment, quizzes, Sky Sports and even a late night money exchange.

Whiskey Jar
If you are missing your food at home this is the place to go for your Scottish, English and Irish breakfast.

Don’t know of many gay bars but in Las Americas there are at least 3 in the Commercial Centre Salytien
Geminis
Chaplins
The Cellar (a British owned Gay bar) 

For more information on the Gay scene check out the link http://www.tripadvisor.co.uk/Travel-g...

Tramps
Upper Floor, Starco C.C.
Not the biggest club by size but certainly the biggest club by popularity on the island and its not hard to see why.   It offers an amazing clubbing experience until 5am. There are three areas for you to choose from. If you want to chill out to funky house on the open air terrace,  if you want something heavier head inside to the main arena. Or the R'n'B room playing all the best in new and old.
On a normal evening entry is free but when Named DJs are appearing there will be an entrance fee of around €15.
 
The Players Lounge
Upper floor, Starco C.C.

This place makes a refreshing change from the other bars around Veronicas and Starco. Because it has gone back to basics and offers cheap drinks, decent music and no 2 for 1 offer price confusion!

Yates Showbar
CC Starco

Another good party bar with varied music. Whether you want to dance away to your favourite cheesy classics or sing along to the all time anthems, you will have no complaints about this bar.