Hi USAprof, I thought I'd chime in here.
My partner and I stay in the UK (he's british) because he has a chronic condition (haemophilia) which makes any move to the usa and increase in pay really tough to figure out, because health care costs would be astronomically high for him. But he pays nothing here -- he falls under the NHS exemption for prescriptions. So that's definitely something to consider with your partner. Neither one of us has private health coverage. I haven't run into any problems at all with the NHS, except with dental which is sort of separate anyway.
Echoing what others have said, it's not really right to do a figure-for-figure cost analysis, because the lives are just different. You'll live in a smaller house or a flat. Grocery costs are cheaper (for me, anyway!) than in the USA. Eating out is more. Love the theatre, and west end shows are far cheaper than broadway. Movie tickets are similar prices. Bike lanes are better than in the USA. Electricity is more, but efficiency is valued.
For comparison for you, I'm living more expensively and in London rather than the others posted here:
Rent: £1350 for a large 1-bed flat in SW London, including large private garden (I love this flat and will never give it up)
Cell phone: 1 iphone at £32/month (1GB data, unlimited calls/texts), 1 android at £18/month (unsure what his plan is)
Cable + TV license: we don't do TV, just iplayer occasionally, so free
Council tax: £60ish/month (including wandsworth+london tax)
Electric/gas/water: water was £450ish for the full year. Electricity is about £100 every 3 months, gas £50 every 3 months
Renters insurance: £15/month (through john lewis)
Transportation: we don't drive, and we cycle most places. Probably about £80 spent monthly on the tube between us though. (more than that for me, but work reimburses a bunch of it)
Pets: we're considering getting a cat as our flat allows it, but concerned about future moves. far fewer rentals allow pets here than in the USA.
Groceries/eating out: about £60-80/week, including wine. My partner's a great, great cook and it's cheaper to get him fancy ingredients than eat out. We eat out maybe once a month.
Student loans: I have a fair amount of USA student loan debt. I pay around £500/month -- slightly variable because of the exchange rate changing, but I transfer over that much each month.
Gym membership: local leisure centre for me is £25/month. Civil service gym for him is £5/month.
We live pretty okay. Take trips to the continent once or twice a year. Rarely to the USA though, we'll be going for only his second time for an extended visit this january. I get 23 days (excluding public holidays) paid time off, he gets 28, exclusive. Combined income pre-tax is between £55-60K.
