What is the etiquette for tipping in London ?
This is nearly an endless discussion with a wide range of opinion. In London and most of Europe we tip in the range of 10%, perhaps round up the bill, or leave the change. I t is my understanding is that Europeans tip much less than t he US or not at all. My personal preference is leave something and generally around 10%.
Here are a couple of websites that might help:
https://www.visitlondon.com/traveller-information/essential-information/money/tipping
What sort of thing do you want to tip for?
With regard to London, most restaurants add a “discretionary 12.5% service charge” to the bill. You can ask for it to be removed. I always just pay it, but I don’t add an additional tip beyond that.
I pretty much never tip in the UK, as it's not really part of the culture. As has been noted, restaurants will normally add a service charge (which I do always pay), so that covers dining out. In terms of accommodation, I stay at a London club that adds a similar amount for the staff Christmas fund.
I do tip in countries where it's expected, including some continental European countries like Austria, for example.
Restaurants: vast majority add 12.5% service charge. By law you are allowed to ask for this to be removed. In reality very few people would do this. No additional tip necessary. If no service charge then I’d tip 10-12%.
Pub where you order at the bar: no tip required. Can stick a couple of coins in the tip jar if you want.
Pub with table service: I would tip 10% if they don’t include a service charge. Many do.
Taxi driver: couple of pounds tip quite usual but not required.
I would try to tip anybody who carried my bags but I rarely stay in places with this level of service and often don’t have cash anyway!
Helens advice is bang on, exactly what I experienced over the years.
The only thing I will add, is with the rise of contactless pay (and the resulting lack of coin or cash in your pocket) you will see "scan to tip" signs up in places where you might be inclined to tip, but have no cash. This would be coffee shops, pubs, even the buskers around town and in the Tube, as well as donation points for museums and other causes. Basically you scan the code, your Google or Apple Pay gets hit for a GBP or two. Again, you are not in any way obligated to tip, but if you really want to, it is an easy way to do so in a cashless society.