US tax laws have some influence on this ... most of us who will have $1 million or more by retirement have been putting that money into tax deferred investments ... namely IRAs, 401Ks and similar funds. The UK equivalent may be a PPP (personal pension plan). If we pull money too early then we get hit with huge tax penalties. We can start pulling money out of them after retirement at age 55 or at age 59.5 regardless of retirement status without the penalties. The money will then be taxed the same as our other income. There's also another savings option called a Roth IRA where you pay your taxes in advance and your interest is tax free ... but with the same age requirements for pulling out your cash. Looks like the UK equivalent may be an ISA. And most of us middle class types won't be reaching the $1 million mark until we are near retirement age anyways.