You need to do dead reckoning to pass the UK PPL skills test.
Not even that. I would say you need to 'demonstrate the skill'. Having done skills tests around Heathrow and Gatwick, in practice I track crawled around the zones, and my examiners knew it. You aren't allowed to use GPS/VOR/DME on the first leg, and it's no good making your mid-course correction from inside the zone you just busted...