Crucially, they differ in how they are calculated and the ages of workers that they apply to.
Labour leader Jeremy Corbyn claims they do. Two academics assessed the facts.
Boris Johnson says so. But the reality about EU minimum wages and the effect on migration is more subtle.
Cities don't have much control over national policies – but that doesn't mean there's nothing they can do.
Plans to stop universal credit payments in favour of a 'national living wage' will not address the long-standing poverty of many people in paid employment.
Low-income families will actually end up worse off, if Osborne's cuts to welfare continue.