How much you'll spend in Tenerife will depend on your plans and your accommodation choice. If you're budgeting for meals, day-trips and maybe some watersports and club nights out, then £40-£50 per day should give you ample, bearing in mind that you can pop the ATM if funds are running low.
Do I need cash in Tenerife?
Only the most remote restaurants and bars won't have a card reader. Mind you, you'll often find that some shops and restaurants prefer cash for small purchases. So, it's always useful to carry a few euros to help with budgeting and emergencies. And that'll also be handy for tipping waiters and drivers.
Is tipping customary in Tenerife?
In Tenerife, it is not considered rude not to leave a tip, as it is understood to be voluntary when the professional service provided is good. The standard at bars and restaurants is to leave a tip of 5 to 10% of the bill, depending on how much it adds up to.