Tips (gratuities, bahşiş in Turkish) are generally modest in Turkey (a small percent of the price paid). Because Americans tend to tip big, leading Turkish tourism industry workers have been led to expect big tips from Americans who travel to Turkey.
The common practice in Turkey is that you cannot include the tip on a credit card charge. You should tip in cash money and, in most cases, hand the tip directly to the person who has served you as a nice gesture. (In some establishments, any tip you leave on the table will end up in the owner's cash register, not in the server's pocket.)
Although the person you tip would probably prefer Turkish liras, you may tip in any currency as long as you give notes/bills (paper money). Don't give foreign coins, as these cannot easily be exchanged for Turkish lira; instead, use small bills. US Dollars, Euros, and British Pounds would all be acceptable, as well as local currency.
Turkish food is one of a kind worldwide, so tipping at restaurants has become much more common and expected throughout Turkey. A tip of 10% - 15% is considered appropriate at most places. You can leave it in cash on the table or ask the waiter to add it to the bill.
In some high-end restaurants and cafes, a service fee (usually 10%) might be automatically included in the bill. This service charge is for the services provided by the staff and may take place of or supplement a tip.
For tipping hotel staff, porters are happy with $1 to $2 per bag. Housekeeping and room service staff are hard-working and deserve your generosity. In moderately-priced hotels, $3 to $5 per day is well-deserved and greatly appreciated by hotel staff.
In some hotel breakfast rooms, restaurants, and/or at the reception desk you may see a Tip Box. This is the appropriate place to express your appreciation to the waitstaff or hotel concierge for good service.
Tipping tour guides and drivers on organized tours are at your discretion. Certainly, especially in major towns, guides, and drivers hope for tips, but a good guide or driver will not think less of you for not tipping; and a bad guide or driver deserves no tip.
Remember, this is a tip meant to signify good service or to receive better service (if that's what you've received), not his/her payment (which you will already have paid for by paying for your tour). That being said, the guide would appreciate $20 to $40 USD per day from a small group, less for the driver.
This is the total tip for the entire group, not the tip per group member. So for a 10-day tour, the guide would be given an additional tip of $200 to $400 total from the group as a recognition of his/her excellent service.
If an on-site worker performs some special service, such as giving you a personal tour, an additional tip equivalent to a few dollars is appreciated.
Airports/Train & Bus Stations
Every airport, bus station (otogar), and train station (gar) has an official tariff for porters, which should be posted prominently. Of course, you probably won't see it. As a general rule, give a small tip of about $1-$2 per bag, which should be plenty. If you actually end up underpaying according to the official tariff, the porter will surely let you know for an additional tip.
To tip taxi drivers, Instead of tipping, just round the fare upwards to a convenient amount. For example, if the fare is TL107, round it up to TL110. Taxi drivers usually do not carry large amount of change so it's always wise to use smaller bills to pay. You also need to pay for the fare in Turkish liras rather than a foreign currency. It's not necessary to tip taxi drivers, unless you have hired a taxi driver for a longer journey, similar to a tour guide, you may be inclined to give a small gratuity.
For private transfer services, no tip is required. However, if you wish to tip—if the driver has been particularly providing exceptional service —5% to 10% of the fare is appropriate.
Turkish Bath (Hamam)
Turkish baths are another service many tourists choose to experience the local culture. When you visit Turkish baths or Hamams, at the end of your bath, all the attendants (and there are lots of them) will line up to "bid you goodbye" and expect a tip (if the service has been good). Share out among them about 15% of the total price of the services you've used.
You will benefit from Turkish hospitality when you come to Turkey. While the country doesn't have a strict tipping culture, some Turkish people may expect to get a small tip when it comes to tourists. However, you don't have to tip anyone if you don't wish to. If you ask for assistance or directions on the street from local shopkeepers or pedestrians, they don't expect a tip.
That being said if you feel generous when visiting Turkey, Turkish people will definitely appreciate a small tip for good service. Anything up to $5 will be more than enough. Other than tipping hotel staff and tour guides, probably won't tip in Turkey that often.
Beware of Scammers
Another thing to look out for is people who try to get tips/donations from tourists by tricking them. This is not special to Turkey and rather applies worldwide. Wherever you go, you can spot people who offer you free gifts. However, if you accept their 'gift,' they will request a generous tip/donation.
These people don't deserve to get your money, and they are a disgrace to their country. So, when you visit a foreign country, refrain from accepting anything free!
Tipping in Turkey is quite modest compared to the tipping culture in the USA. When tipping, it is up to the customer to decide based on the service they've received. Generally, $1-$5 for small services, such as hotels, waiters, etc., is accepted; meanwhile, you can tip up to 15% for bigger services, such as guided tours and restaurants. If you received bad service or already paid service charges, don't feel an obligation to leave a tip.
In Turkey, tipping is not the norm, so you are not obligated to tip, however, tips are always appreciated.