When I have visited Stockholm I have been told that tourist guides and waitresses/waiters, bellboys are not to be tipped. The last time that I visited Stockholm I had the god luck of being able to have an inofficial discussion with a touristguide. She told me that these persons (tourist guides and waitresses/waiters, bellboys etc) have the really lousy wages just like every where else in the world. So, don't be shy with your tipping. The person that says that it would offend the receiver is probably not a tourist guide and waitress/waiter or a bellboy himself.
In Stockholm as in the rest of Sweden, tips are supposed to be included on the check at restaurants. However, more and more people still tend to tip a little. If you are unhappy with something, then you shouldn't give a tip, but if the service was good and the food was good, give a little. 10 percent is a good amount.
If your bill ends up at 243 kronor though, you will probably give 250 even if the service was bad, seems petty to scramble the coins...!
In hotels and restaurants a service charge is included in the bill and a further tip is not expected, although it’s usual to round up the bill to the nearest 10 or 20 Skr.
Taxi drivers usually get an extra 5 Skr but this is optional.
Cloakrooms at restaurants and clubs charge about 10 Skr.
Tipping for special services provided by hotel staff is fine but not expected.